A Scotland Yard statement said:
Four of the five police officers who were mauled by a dog during a raid in east London have been described as being in a serious but stable condition.
The remaining PC suffered minor injuries.
Five police officers have been taken to hospital after being mauled by a dog during a raid.
The constables were attacked by a "pit bull-type" animal as they attempted to arrest a suspect in east London, Scotland Yard said.
A dog unit and firearms officer were called before the dog was "contained and subsequently shot dead", the force added.
The man - in his 20s - was arrested and is in custody.