Armed police swooped on a flat in east London and dragged two suspects away, according to witnesses.
Dozens of officers carrying guns and with their faces covered were seen raiding a property above a shop in East Ham at around 2pm on Sunday.
Witnesses say two men were dragged out and taken away in police vans.
It comes after seven people were killed and 48 injured in the London Bridge and Borough Market terror attacks on Saturday, with 21 fighting for their lives in hospital.
MORE: Seven dead, at least 48 injured, three attackers killedLocal resident Malik Rouf, 30, said one of the men inside the flat jumped out of a first floor window on to a ledge before he was pulled back inside.
'He was about 30 years old and in a vest - he tried to go out the window but the officer was standing with a gun saying 'get back in, get back in''
'He was dragged out and put in a police van.'
He said both men had shaved heads, full beards and one was wearing Islamic robes.
MORE: Witnesses describe seeing speeding vehicle veer into crowds in LondonA line of police tape was put in place around the flat and crowds of locals looked on as officers guarded the perimeter.
MORE: Leaders and politicians from Norfolk and around the world reactWitness Shimma Ali, 32, said it was terrifying to see dozens of armed officers in the street.
'I heard a woman screaming and 20 officers with guns - there was a sniper across the road trained on the window,' she said.
'Then a young black man, barefoot and in pyjamas, came out the window.
'They were shouting 'we will shoot you if you don't go back in'.
'I thought he was going to get shot - the police officer had his gun on him and was ready to shoot.'
She added: 'It's absolutely terrifying - we don't expect it in this area, it's so multicultural and diverse, there's no racism.'
MORE: Neighbours report hearing shots fired as 12 are arrested
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