LONDON - British police investigating the Manchester attack carried out a controlled explosion at an address in the south of the city early Thursday.
Seven people have been arrested so far in the investigation into Monday's suicide attack at a pop concert, which killed 22 people and wounded dozens of others.
The perpetrator, named as 22-year-old Salman Abedi, was born and brought up in the south of Manchester, Britain's third city.
"This morning we have been carrying out searches at an address in the Moss Side area during which a controlled explosion took place," Greater Manchester Police said in a statement on the overnight raid.
"These searches are connected to Monday's attack on the Manchester Arena, but this is a fast-moving investigation and we are keeping an open mind at this stage.
"As it stands, six men and one woman have been arrested in conjunction with the investigation and remain in custody for questioning."
Photos: Explosions at Ariana Grande concert in Manchester
The seventh arrest was made Wednesday in the town of Nuneaton, central England, widening the probe as the previous arrests were all in the Greater Manchester area of northwest England.
The fifth arrest, made in Wigan outside the city, saw armed police swoop on a man and the town centre put in lockdown.
He was carrying a package which police took away for assessment.
Soufiane Hamdadou, the owner of nearby restaurant Fat Olive, said he saw police with machine guns and covered faces on the street.
"I heard shouting and screaming and looked out of the window and saw a man getting wrestled down to the ground," he said.
"It was undercover police and they were armed with balaclavas on."
"The man had a red bag and the police sealed off the whole area and moved the bag to the other side of the road," he said, adding that a man in forensic garb then examined it.