Authorities have identified the suicide bomber as Salman Abedi, 22, a British national whose father comes from Libya. Police say Abedi received help with Monday's attack on an Ariana Grande concert.
Monday night's attack at an Ariana Grande concert in Manchester, England, left 22 people dead. Friends, family and schools have begun reporting their names.
As more of the victims of Monday's suicide bombing in Manchester are identified, an intense police investigation into the bomber's background and contacts continues.
Salman Abedi's relatives were reportedly taken into custody in Tripoli. In Manchester, police arrested four more people. "I think it's very clear that this is a network," the city's police chief says.
The president made the remark after the pope presented him with a medallion featuring an olive branch. "I give this to you so that you can be an instrument of peace," the pope told him.
Hours before the vigil, British Prime Minister Theresa May announced that another attack could be "imminent." From around the world, people expressed condolences for the bombing victims.
Steve Inskeep talks to Kim Darroch, the British ambassador to the U.S., about the aftermath of the suicide bombing at the Ariana Grande concert in Manchester, England, Monday night.
The bishop who will moderate a chat between former President Obama and German Chancellor Angela Merkel discusses its theme:"Being Involved in Democracy: Taking on Responsibility Locally and Globally."