Borough High Street and Newcomen Street were cordoned off on Sunday morning as police investigated a large-scale fight which took place in the early hours.
Police were called just after 3.30am on Sunday to reports of a large fight in Borough High Street.
Nine men were taken to hospital – some suffering from stab wounds – and are being treated at various South London hospitals.
According to police, none of the injuries is thought to be life-threatening.
A New Scotland Yard spokesman said that nine people have been arrested in connection with the incident.
On Sunday lunchtime a police cordon remained in place across Borough High Street between the Union Street junction and St George the Martyr church. Police were also examining a crime scene in Newcomen Street close to the King's Arms pub.
Anyone with information should call police on 101 or Crimestoppers on 0800 555111.