A centre set up to aid victims of the London bombings has been helping friends and family trying to trace 31 people missing since Thursday.
Tessa Jowell has visited the centre
The centre in the Queen Mother Sports Centre, in Vauxhall Bridge, opened on Saturday to offer 24-hour care.
Dozens of family liaison officers have also been supporting relatives of the dead and critically ill.
And they are also to provide assistance to the relatives of foreign nationals who were victims of the attacks.
Those attending the centre are being asked to provide ID and those attending are asked not to bring more than three people with them.
Culture Secretary Tessa Jowell, who has been put in charge of providing government support for victims' families, visited the centre on its opening day.
"This is a centre for families. It is intended as a sanctuary for families," she said.
"This is their safe place in order to come to talk, to get more information and just a place where they can be with other people who are going through the same personal nightmare as they are."
But she said the process of identification would take a long time, as police needed to make sure identifications were accurate.
"Everybody understands the agony these families are going through... there is no delay in this."
The centre is operated by Westminster Council with support from the Metropolitan Police.
Red Cross "be-frienders", members of the Salvation Army, social workers and representatives from the Women's Royal Voluntary Service and Victim Support are present at the centre.
People wanting to volunteer are asked not to visit the centre.
Witnesses are asked not to present themselves to the family reception centre, but instead call the anti-terrorist hotline on 0800 789 321.