Neighbours say the flat door in Greenwich was smashed open by balaclava-wearing police armed with machine guns.
Officers were heard shouting "get down on the floor". Two women thought to be sisters were handcuffed and led away.
A teenage boy, a toddler and a baby were also taken away.
This video shows the clash between Justin Bieber and photographers outside his London hotel.
These pictures show Justin Bieber's scuffle with a photographer outside his London hotel.
Here is a transcript of the scuffle between Justin Bieber and photographers outside the star's London hotel:
Bodyguard: Watch out, give us some space guys.
Photographer: OK, OK.
[Bieber pushes photographer]
Photographer: Easy! Easy! That's assault. That's assault.
Bodyguard: Yeah, but you're in our way. Relax.
Photographer: No, I moved out the way. F-----g little c---. That's assault. F--k back off to America. F-----g little moron.
Bieber: What the f--k did you say? What did you say? I'm gonna f-----g beat the f--k out of you.
Photographer: You heard what I said. Lose your f-----g bouncers.
The singer Justim Bieber has tweeted about his altercation with a photographer as he left a hotel in central London:
In the footage, Bieber is seen pushing a member of the press out of the way as he climbs into a waiting car.
He then gets out of car and pushes the cameraman again, shouting a stream of expletives.
Watch the video in full on the Channel 5 News at 5pm.
Pop star Justin Bieber posted picture of himself from his hospital bed and said he was "getting better listening to Janis Joplin".