Police have released a CCTV image of the four London bombers together as they set off on their deadly mission.
The four men were pictured entering Luton rail station at 0720 BST on Thursday 7 July on their way to London.
The three explosions on London Tube trains and one on a bus killed at least 55 people, including the bombers.
A counselling centre has been set up to help victims, transport staff and relatives deal with the after-effects of the attacks.
Authorities in Pakistan say they are placing Islamic religious schools under closer scrutiny, after reports that one of the bombers attended one last year.
Police confirmed the names of all four bombers - Muhammad Sidique Khan, 30; Shehzad Tanweer, 22; Hasib Mir Hussain, 18 and Germaine Lindsay, 19 - for the first time on Saturday.
The CCTV picture was released in an attempt to find out more about their final movements.
Peter Clarke, head of the Anti-Terrorist Branch, said: "The investigation continues on many fronts, but we have been very grateful for the contribution made by the public in response to our previous appeals.
"However we still need to find out more about these four men and their movements, both on the morning of the bombings, and in the days and weeks beforehand."
It is thought Hussain was responsible for the bus bombing, in which 13 people died, Khan the Edgware Road blast that killed six people; Tanweer for the Aldgate blast, which killed six, and Lindsay for the Russell Square explosion where 26 people were killed.
The move to monitor Pakistan's religious schools - known as madrassas - came after reports Tanweer attended one of them last year.
Pakistan's Interior Minister Aftab Khan Sherpao told the BBC far closer scrutiny would be given to madrassas preaching extremist views.
In other developments:
- The father of Germaine Lindsay was quoted on Jamaican radio saying he was surprised by his son's actions. Nigel Lindsay, 45, said he had recently resumed contact with his son after many years and that he was "quiet and calm"
- Ten addresses in West Yorkshire and one in Aylesbury, Buckinghamshire, have been searched. Seven of the 10 West Yorkshire searches are still ongoing
- Police have extra time to question a man, arrested on 12 July on suspicion of the commission, instigation or preparation of acts of terrorism, and held at a central London police station
- Police have taken more than 800 witness statements and received 3,500 calls to the anti-terrorist hotline
- The wreckage of the bombed number 30 bus has been moved from Tavistock Square in central London for further forensic examination
Shadow foreign secretary Liam Fox said there was no direct link between the bombings and the Iraq war.
Al-Qaeda existed long before the war, "and even when the British and American troops are no longer in Iraq, we will still be at risk from these people", he said.
"These people detest the West. They detest our way of life, our democracy, our capitalism, all the things we take for granted.
"There is no way we can ever guarantee our safety as long as these people are out there."
Sadiq Khan, the British-born Muslim MP for Tooting, south London, said it was very dangerous to suggest the attacks were purely driven by the Iraq war.
There was no point in looking for a "quick-fix solution", he said.
New terror laws seen to target one section of the population disproportionately could help recruit new terrorists to the extremist cause, Mr Khan added.
"Will... the person you have wrongly stopped and searched... or put under control order... come forward and assist you, the authorities, in fighting terrorism and crime? That is the concern."
The Lord Chancellor told BBC News under new laws people "attacking the values of the West" and "glorifying the acts of suicide bombers" would be imprisoned for "long periods" and "deported wherever possible", but no law could stop terrorism altogether.
"The evil ideology driving this is getting to the hearts and minds of a very small number of people," Lord Falconer added.
"We need to be effective in dealing with them... to make it absolutely clear there will be no compromise."
Shadow home secretary David Davis told BBC News the bombers had intended to "drive a wedge into British society", leaving Muslims alienated "and in that way act as a recruiting sergeant for more young men in the future".
"We have got to stop that."
Mr Davis urged Muslim leaders to be "very, very firm".
"They should not allow any doubt whatsoever these sort of events are condemned - wherever they happen, whatever the excuse - it is always evil to undertake suicide bombing."
On Saturday, Tony Blair said it was time to stand up to the "evil ideology" behind the London bombings and other attacks.
He said such violence was not a response to any particular policy or injustice, but was a "fanaticism" that had to be confronted.
Germaine Lindsay (above): Jamaican-born man living in Buckinghamshire. Believed to have carried out King's Cross attack.
Mohammad Sidique Khan: Aged 30, from Beeston, Leeds, recently moved to Dewsbury, married with baby. ID found at Edgware Road blast site.
Hasib Mir Hussain: Aged 18, lived Holbeck, Leeds. Reported missing on day of bombings. Said to have turned very religious two years ago. ID found in No 30 bus.
Shehzad Tanweer: Aged 22, born Bradford, lived Beeston, Leeds. Studied religion in Pakistan. Forensic evidence linking him to Aldgate blast.
The families of Khan, Hussain and Lindsay have all issued statements expressing their shock and sadness.
Lindsay's wife Samantha Lewthwaite said: "I am trying to come to terms with the recent events. My whole world has fallen apart, and my thoughts are with the families of the victims of this incomprehensible devastation."
The family of Hussain said: "Our thoughts are with all the bereaved families and we have to live ourselves with the loss of our son in these difficult circumstances."
Khan's family said: "We are devastated our son may have been brainwashed into carrying out such an atrocity."
Tanweer's uncle said the family had been "left shattered" by news of his involvement.
British police are now searching for those who may have helped the bombers carry out the attacks.
One house being searched in Leeds is linked to Egyptian biochemist Magdi Mahmoud al-Nashar, 33, who was arrested in Cairo as part of the inquiry into the bombings. He has denied any involvement.
The bombed bus was moved from Tavistock Square on Saturday
Egypt's interior minister said press reports linking Mr al-Nashar to al-Qaeda were "groundless" and based on a hasty conclusion.
Other properties being searched are the Holbeck home of Hussain, the Dewsbury home of Khan, and the Beeston home of Tanweer.
Lindsay lived in the property being searched in Aylesbury.
On Saturday police sealed off and searched a house in Tempest Road, Beeston, Leeds, not far from where Tanweer lived.
On Sunday, public vigils took place in Edinburgh and Glasgow to remember the victims of the bombings.
The gatherings, organised by a groups including the Muslim Association of Britain, are also aimed at showing opposition to Islamophobic attacks since the explosions.
Police are urging anyone with information that could help their investigation to call the confidential Anti-Terrorist Hotline on 0800 789 321.