Britain says some of Manchester bomber's network potentially still at large

Armed police officers stand on duty in central Manchester, Britain, May 28, 2017. REUTERS/Phil Noble

MANCHESTER, England (Reuters) - Members of Manchester suicide bomber Salman Abedi's network are still potentially at large, British interior minister Amber Rudd said on Sunday, after the terrorism threat level was lowered because of significant progress in the investigation.

Police said they have arrested a large part of the network behind the bombing, which killed 22 people at a concert hall, and four more men were arrested over the weekend as police continued to close in on the group.