Three men were arrested in the south of Manchester city on suspicion of being connected to the attack that hit a concert in the city, British police said on Wednesday.
On Monday evening, 22-year-old Salman Abedi detonated a bomb as fans were leaving an Ariana Grande concert at Manchester Arena, killing 22 people and injuring at least 64.
“Three men have been arrested after police executed warrants in South Manchester in connection with the ongoing investigation into Monday night’s horrific attack at the Manchester Arena,” said Greater Manchester Police in a statement.
Abedi’s 23-year-old brother was arrested on Tuesday.
Interior minister Amber Rudd told press that it was likely that Abedi was not working alone and that he was up to a point known to British secret services, BBC reported.
The country’s terror threat alert was moved up to its highest “critical” level, meaning more attacks may be imminent.
The Defence Ministry said the change of guard ceremony at Buckingham Palace and tourist visits to Parliament would be cancelled until the threat level was lowered.
Investigations were ongoing to discover potential motives behind the attack, which was been claimed by the Islamic State terror group.