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Police: People linked to Manchester bombing could still be at large

LONDON -- British police said Thursday that the man who bombed an Ariana Grande concert in Manchester was not part of a large network, but other people involved in the attack may still be at large.

British police raid houses in Manchester

Russ Jackson, head of counterterrorism policing for northwest England, said Thursday that police may make more arrests in the investigation.

Salman Abedi, a Briton of Libyan heritage, detonated a backpack bomb as crowds were leaving Manchester Arena on May 22, killing 22 people and himself.

In the days after the attack, police arrested 22 people on suspicion of terrorism offenses and said they had rounded up a large part of Abedi's network. But all the suspects were subsequently released without charge.

Jackson said detectives want to question Abedi's younger brother, who has been detained in Libya.