A year after the train attacks in Madrid on 11 March, 2004, the investigation into the attack continues.
The rush-hour bombings of four Madrid trains killed 191 people
Only one person has been convicted of involvement in the attacks so far.
Of more than 70 people arrested in the course of the investigation, at least 22 remain in detention on provisional charges. They must be prosecuted within two years of the date of their arrest. Two suspects are in custody overseas.
About 17 suspects have been released but must report to authorities regularly and have surrendered their passports.
A further seven suspects died in an apparent suicide explosion in the Madrid suburb of Leganes on 3 April, 2004. And between five and eight suspects remain on the run.
Most of the suspects who have been provisionally charged are Moroccans, but they also include others from Spain, Algeria and Lebanon. The most prominent are listed below.
El Gitanillo (Little Gypsy): Spanish, arrested on 14 June, 2004
On 16 November he was sentenced to six years in a juvenile detention centre, followed by five years under police surveillance, for stealing and transporting explosives used in the attacks.
The 16-year-old, who cannot be named, was the first of the suspects to stand trial. He pleaded guilty to stealing 20kg (44lb) of explosives. He said he was paid $1,200 for his work.
Jamal Zougam: Moroccan, detained on 13 March, 2004
Mr Zougam, 30, who owns a mobile phone shop in Madrid, is a prime suspect.
Jamal Zougam is said to have links with Islamic terror groups
He is accused of multiple counts of murder, attempted murder, stealing a vehicle, belonging to a terrorist organisation and four counts of carrying out terrorist acts.
Spain's El Pais newspaper says three witnesses have testified to seeing him leave a rucksack aboard one of the bombed trains.
Jose Emilio Suarez Trashorras: Spanish, detained on 18 March, 2004
Mr Trashorras, a former miner, was accused of supplying some of the explosives that were left in backpacks on four trains crowded with early-morning commuters.
Mr Trashorras is accused of providing explosives
He also faces multiple counts of murder, as well as attempted murder, robbery and terrorism charges.
Rafa Zouhier: Moroccan, detained on 24 March, 2004
Accused of collaborating with a terrorist group.
Basel Ghayoun: Syrian, detained on 30 March, 2004
He is accused of being one of the main architects of the attacks, and is accused of multiple murders, attempted murder, and belonging to a terrorist organisation.
Two witnesses are reported to have recognised Mr Ghayoun on one of the trains that was attacked.
Hamid Ahmidam: Moroccan, detained on 30 March, 2004
Mr Ahmidam is said to have lived in a house outside Madrid where investigators suspect the bombs were prepared.
According to Spain's El Pais newspaper, police found the fingerprints of at least 10 people - including some of the other suspects - in the house.
He is accused of collaborating with a terrorist organisation.
Otman El Gnaout: Moroccan, detained on 2 April, 2004
He is accused of collaboration with or membership of a terrorist organisation.
A mason by trade, he is believed to have worked at the house where investigators believe the bombs were prepared.
Abdelilah El Faoual El Akil: Moroccan, detained in the Spanish enclave of Ceuta in North Africa on 2 April, 2004
He is reported to have been at the house in Chinchon, in Madrid Province, where the bombers are thought to have planned the attacks.
He also allegedly bought a car that was used to go to Asturias to collect explosives used in the attacks.
Rachid Adli: Moroccan, detained 6 April, 2004 near Madrid
Reports say he admitted meeting Jamal Zougam, Jamal Ahmidan and Jose Emilio Suarez.
Fouad El Morabit Anghar: Moroccan, detained for the third time on 6 April, 2004
The student has been provisionally charged with collaborating with a terrorist organisation.
Investigators say he was in telephone contact before and on the day of the attacks with most of the suspects who have either been arrested or who are now dead.
Saed El Harrak: Moroccan, detained 6 May, 2004
His telephone number was found in the debris of the flat in Leganes where several suspects died in an explosion on 3 April, 2004. He is reported to have held telephone conversations with several of the suspects before they died. He was charged with collaboration with a terrorist group and ordered to remain in detention on 10 May 2004.
Rabei Osman Sayed Ahmed, Mohamed "The Egyptian": arrested in Milan, Italy in a joint anti-terror operation between Italy, Spain, France and Belgium on 8 June 2004
He is suspected of having played a key role in the 11 March 2004 bombings. Some reports say he is the leader of the Egyptian cell of al-Qaeda. The 33-year-old was extradited to Spain last December.
Rabei Osman Sayed Ahmed is known as The Egyptian
Emilio Llano: Spanish, detained on 9 June, 2004
Foreman from the Conchita mine where explosives used in the attacks are said to have come from. Arrested in connection with the sale of the explosives.
Ivan Granandos Pena: Spanish, arrested on about 10 June 2004
Also accused of supplying explosives. Released from jail on 15 December, 2004 on 6,000-euro ($7,900) bail on orders that his passport is confiscated and that he presents himself weekly at court.
Raul Gonzalez Pelaez: Spanish, arrested on 11 June 2004
Mine worker arrested on suspicion of helping steal explosives for the attacks.
Nasredine Bousbaa: Algerian, arrested in Madrid on 1 July 2004
Accused of receiving nine telephone calls from key suspects days before the attacks. He was released from custody on 15 February 2005 on 6,000-euro ($7,900) bail. He has been ordered to present himself periodically at court.
Abderrahmeb Hammadi Afandi: Spanish of Moroccan origin, arrested on 12 July, 2004
Semaan Gaby Eid: Lebanese, arrested in Carabanchel on 28 July, 2004
Accused of links with suspected co-ordinators of the Madrid attacks.
Faisal Alluch: Moroccan, detained 3 November 2004
Detained, released and finally detained again last November. Reports say he is suspected of hosting meetings of some of the main co-ordinators of the attacks at his home. He is accused of collaboration with an armed group.
Antonio Toro: Spanish, detained for second time on 2 December, 2004
The former miner is accused of supplying explosive substances and collaboration with an armed group.
Adnan Waki: Syrian, detained 11 December, 2004
Accused of links with the group of seven who apparently blew themselves up in a Madrid suburb on 3 April 2004.
Interior Minister Jose Antonio Alonso said Adnan Waki was "an important person" in the structure behind the bomb plot.
Hasan El Haski: Moroccan, detained in Canary Islands 11 December, 2004
Suspected leading member of the Moroccan Islamic Combatant Group, alleged to have played a part in the train bombings, and to have helped prepare the attacks.
Charged with 191 counts of murder, 1,000 counts of attempted murder and membership of an armed group. Ordered to remain in detention.
Brahim and Mohamed Moussatten: Moroccan, detained 1 February, 2005
The two brothers, both in their early 20s, were detained with their parents Allal Moussaten and Safia Belhadj in Leganes, a southern Madrid suburb where the family lives. It was also the scene of the 3 April, 2004 explosion in which seven other suspects died.
Five days later, the brothers were charged with collaboration with a terrorist group - thought to be the Moroccan Islamic Combatant Group, which authorities said played a part in the train bombings. Their parents have been released. Their uncle is Youssef Belhadj (see below).
Rachid Mohamed Kaddur: Spanish, detained 3 February 2005
Authorities say he met Abdennabi Kounjaa the day before the attacks. Provisionally charged with collaboration with a terrorist organisation, and ordered to remain in detention on 9 February, 2005.
Rachid Bendouda ("El Gordo"): Moroccan, detained 2 Feb, 2005
Said to have close links to the suspected perpetrators of the attack and to have met with Abdennabi Kounjaa the day before the attacks.
Provisionally charged with collaboration with terrorist group and ordered to remain in detention.
Youssef Belhadj: Moroccan, arrested 1 February, 2005
Held in Belgium on a Spanish arrest warrant and awaiting extradition to Spain.
Authorities believe Youssef Belhadj could be Aby Dujanah, al-Qaeda's purported spokesman who claimed responsibility for the Madrid attacks on a videotape days after the attacks. He is also thought to be a member of the Moroccan Islamic Combatant Group, which authorities said played a part in the train bombings.
He is thought to have stayed with his nephews Brahim and Mohamed Moussatten (see above) in a Madrid suburb days before the attacks.
Hicham Ahmidan: Moroccan, detained 25 March, 2004
Held in Morocco on drugs trafficking charges, but wanted for questioning in connection with the Madrid bombings. He is a cousin of Jamal Ahmidan, who died in the Leganes explosion in April 2004.
Said Berraj: Moroccan
Court documents suggest Said Berraj has al-Qaeda links. At first he was believed to have died in the 3 April, 2004 explosion in Leganes, but authorities now believe he escaped.
International arrest warrants have also been issued for Mohamed Afalah (Moroccan), Abdelmajid Bouchar Moroccan, Daoud Ouhnane (Algerian), Amer Aziz (Moroccan), and Mohamed Belhadj (Moroccan).
SUSPECTS KILLED IN 3 APRIL 2004 BLAST
Sarhane ben Abdelmajid Fakhet ("El Tunecino"): Tunisian
The suspected ringleader of the plot.
Jamal Ahmidan (alias "El Chino" or "Mowgli"): Moroccan
He is also thought to have led the bombers.
Allekema Lamari: Algerian
He was described as the "emir" of the train bombings by the Spanish authorities. In 1997, he was charged with belonging to an Algerian extremist group and was sentenced to 14 years in prison. But he was released two years ago after his sentence was reduced.
The other four are thought to have been part of the group who placed the bombs on the trains. They are:
Mohammed Oulad Akcha and Rachid Oulad Akcha:
Moroccan brothers. Their sister, Naima Oulad Akcha, has been detained by police.
Abdennabi Kounjaa ("Abdallah"): Moroccan