Two more alleged masterminds behind the deadly Madrid train bombings in 2004 have denied any involvement in the attacks that killed 191 people.
Mr Belhadj denied being al-Qaeda's spokesman in Europe
Moroccan Youssef Belhadj denied claims of having links to militant groups and being al-Qaeda's spokesman in Europe.
Hassan el-Haski, another Moroccan, also denied involvement. Egypt's Rabei Osman, a third alleged mastermind, declared his innocence on Thursday.
Twenty-nine people are charged over the blasts in the Spanish capital.
Also on Friday, one of the alleged bombers, Morocco's Jamal Zougam, denied any involvement.
The trial began on Thursday and is expected to last a number of months.
More than 1,700 people were injured in the multiple bomb attacks on four rush-hour trains in Madrid in March 2004.
TRIAL IN FIGURES
29 men on trial
Six charged with 191 counts of murder and 1,755 of attempted murder
One is charged with 192 counts of murder and 1,755 of attempted murder
They face up to 40,000 years in jail each
22 others face lesser terror-linked charges
About 600 witnesses and 100 experts will give evidence
The indictment itself is 100,000 pages long
Investigators in Spain have attributed the attacks to a local cell of Islamic extremists inspired by al-Qaeda.
Mr Belhadj is charged with 191 murders and 1,755 attempted murders.
Appearing in the court on the outskirts of Madrid Mr Belhadj said: "I condemn the attacks and all kinds of violence."
He was arrested on 1 February 2005 in Belgium and later extradited to Spain.
The authorities believe he could be Aby Dujanah, al-Qaeda's purported European 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. The group has also been blamed for the 2003 Casablanca bombings.
Mr Belhadj denied having any terror links, or knowing any of the other key suspects on trial.
"I am a normal Muslim," he said.
Mr Belhadj said two members of his family had named him as a member of al-Qaeda only after the Spanish authorities detained and terrified the whole family.
"They were insulted and threatened that they would be taken back to Morocco," Mr Belhadj was quoted by AP as saying. "So if I were in their shoes... I would have said things like that."
Mr Haski was detained in the Canary Islands on 11 December 2004.
He is also charged with charged with 191 murders and 1,755 attempted murders and he is suspected of being a leading member of the Moroccan Islamic Combatant Group.
However, appearing in the dock Mr Haski said the Moroccan militant group he is accused of leading "does not exist."
"The group is a fiction," he added.
The trial began on Thursday with testimony from Rabei Osman, who denied any involvement and condemned the attacks.
All three of the key suspects answered questions posed by their defence lawyers having refused to answer any from the prosecution.
On Friday, Mr Zougam, accused of being one of the bombers, declared his innocence.
"It's impossible I was there. I was asleep at home," he told the court.
In all, 29 people, most of them Moroccan, are accused of involvement in the train bombing plot, which saw 10 bombs contained in rucksacks being detonated on four commuter trains.
Seven key suspects, including Mr Belhadj and Mr Haski, face charges of murder and belonging to a terrorist group.
Twenty-two others face lesser terror-linked charges including collaborating with a terrorist group and handling explosives. Eleven of them are from Morocco, eight from Spain and one each from Algeria, Syria and Lebanon.
The trial is expected to hear from hundreds of witnesses and police experts.
A verdict is not expected before October.