A murder investigation has been launched following the discovery of a man's body at Partnership House, a disused Waterloo office block.
The Met says that at approximately 12.30 on Monday a member of the public visited a local police station to pass on information about a man's body at Partnership House, a derelict office block at the junction of Waterloo Road and Gray Street.
Police officers searched the building and found a man – believed to be a Polish national in his late twenties – with serious head injuries. He was pronounced dead at the scene.
One eyewitness said that at least 50 people were involved in Monday's operation, "including about 20 police in riot gear".
A post mortem will be held at Greenwich mortuary on Tuesday.
A Homicide and Serious Crime Command team is investigating and an incident room has been set up in Sutton.
Gray Street remained sealed off on Tuesday afternoon.
"We believe the victim has been living rough in the area, probably in the disused office block in which he has been found," says acting Detective Chief Inspector Russell Taylor.
"If this is the case he will be well known to those who work and live within this community. I would ask anyone who has information to either call the incident room or to speak to a member of the local Safer Neighbourhoods Team.
"The incident room can be contacted on 020 8721 4155; if you wish to remain anonymous call Crimestoppers on 0800 555 111."
Eight men aged between 21 and 35 were arrested at Partnership House yesterday. They remain in custody at south London police stations.
The building was previously occupied by a number of church organisations including USPG, SPCK and the Anglican Communion secretariat.