LONDON — Londoners packed churches across the capital yesterday to mourn the victims of last week’s terror attacks, as religious leaders sought to prevent retaliation against Muslims.
Police, meanwhile, announced progress in the effort to recover the bodies of subway riders still trapped underground, but warned that Britain faces more terrorist attacks if the perpetrators aren’t caught.
Three men arrested at Heathrow Airport yesterday under counterterrorist laws were released later in the day without charge, police said.
Police had cautioned against linking the detentions of the men — all Britons — to the explosions at four transit locations during morning rush hour Thursday that killed at least 49 and wounded hundreds.
British reporters said investigators asked European police forces to search for a Moroccan named Mohammed al-Guerbouzi, 44, who had been given asylum in Britain. Europol spokesman Rainer Wenning declined to comment on the reports.
Al-Guerbouzi was convicted in absentia by Morocco in December 2003 in connection with the Casablanca terrorist attacks and sentenced to 20 years in prison. Britain never extradited him.
Mustafa Setmarian Nasar — a Syrian accused of being al Qaeda’s operations chief in Europe and the mastermind of the Madrid railway bombings last year — also was named as a suspect in reports in three major British newspapers.
London’s Metropolitan Police officials said they would not comment on the names of any suspects.
Former Metropolitan Police Chief John Stevens said that the bombers “almost certainly” were homegrown and that Islamist groups were recruiting and training as many as 200 British-born extremists to continue the attacks.
“They are also willing to kill without mercy — and to take a long time in their planning,” Mr. Stevens wrote in the News of the World newspaper, noting that police had thwarted eight attacks in the past five years.
A neat row of bouquets, some bearing cards of sympathy for the victims, lined the steps to St. Pancras Parish Church, just yards from where one of the bombs cut apart a double-decker bus, killing 13.
The attacks “will only make us more determined to live in peace and respect each other and we can all play our part in that,” said the Rev. Paul Hawkins, who spoke of the diversity of culture and faith in London.
“I came because of what happened so close to here,” said Paul Critchton, 59, who passes the church regularly but never before had attended a service.
“I think the vicar struck the right message today between thinking about the people who died and were injured and encouraging people to continue with their lives.”
Britain’s top religious leaders made a joint appearance in the afternoon, appealing to Muslims, Christians and Jews to unite in their condemnation of terrorism and their resolve to fight it.
The gathering included Archbishop of Canterbury Rowan Williams; the Roman Catholic archbishop of Westminster, Cardinal Cormac Murphy O’Connor; Free Churches Moderator David Coffey; Chief Rabbi Jonathan Sacks and Sheik Zaki Badawi, who heads the Council of Mosques and Imams.
They met “to proclaim our wish to resist any form of violence and to work for reconciliation and peace,” Cardinal Murphy O’Connor said.
At the Vatican, Pope Benedict XVI expressed “profound sadness” over the attacks.
“Let us pray for those killed, for those injured and for those dear to them. But let us also pray for the attackers: Let the Lord touch their hearts,” the pope said.
“To those who foment feelings of hatred and to those who carry out such repugnant terrorist actions, I say to you: God loves life, which He created, not death. Stop in the name of God.”
As ordinary Londoners prayed, police and subway authorities continued the grim task of recovering bodies from a rat-infested subway tunnel.
Andy Trotter, assistant chief constable of British Transport Police, told reporters that the figure of 49 included bodies counted in the wreckage between King’s Cross and Russell Square, but “there is a possibility as the search teams go through that we will find more.”
Ian Blair, commissioner of Metropolitan Police, said last week that the death toll was “50-plus.”
Mr. Paddick said yesterday that an unspecified number of bodies had been recovered, but conditions underground were still “very hot, very dusty, very dangerous.” Temperatures in the deep tunnel go as high as 140 degrees.
The deputy police commissioner issued an appeal for videos, photos and cell-phone images that might provide clues to the attackers’ identities, setting up an e-mail address.
Investigators have pored over videotapes from surveillance cameras and photos and asked for help from the public.
Reuters news agency quoted a police source saying investigators also had asked mobile phone and Internet companies to store the contents of voice mails, e-mails and text messages that were in their systems on the day of the bombings.
The source said the only previous such request came after the September 11 terror attacks in the United States but that some companies had warned they might be unable to comply for technical reasons.
Home Secretary Charles Clarke told British Broadcasting Corp. television that Britain faces more attacks if those responsible for the bombings aren’t found.
“The fact is the terrorist threat is a real one as we saw so dramatically and awfully on Thursday,” he said.
“Our fear is, of course, of more attacks, until we succeed in tracking down the gang which committed the atrocities on Thursday, and that’s why the number one priority … has to be the catching of the perpetrators,” he said.