Detectives investigating the death of a man on waste ground in Oxford believe it could be an elaborate and bizarre suicide.

The body of the man - whose identity had not been released last night - was found by a passerby on grassland near the Seacourt park-and-ride, off Botley Road, just after 9am yesterday.

It is understood a knife was found with the body. Officers initially thought he might have been murdered.

However, a source told the Oxford Mail last night that police believed the man, thought to be a student, might have taken his own life.

Detectives are investigating whether the man used the knife, a length of rope and a length of plastic drainpipe to kill himself.

The drainpipe had been attached to the leg of an electricity pylon in the area.

National Grid staff were called in to remove the pipe.

The source said: "If what we believe happened is true, it is one of the most elaborate and bizarre suicides we have dealt with.

"Initially police thought it was murder because of the knife but, through detailed work, we don't believe it is the case."

A postmortem examination was being carried out last night.

Police are asking for the public's help to find out what happened and possibly piece together the man's final movements.

Officers had been alerted to the discovery of the body shortly before 10am. They believe a member of the public found the body at about 9.10am.

Detectives and scenes of crime officers threw a cordon around the area where the body was found in the grass, as a forensic examination of the scene was carried out.

A tent was put up around the body as police teams combed the area for clues throughout the day - although the forensic examination had ended by early afternoon.

Part of the bus lane was blocked off, causing delays for city-bound traffic coming off the A34.

A police spokesman said: "Police are still treating the death as unexplained.

"Anyone with information should contact police on 08458 505505 or Crimestoppers on 0800 555111."

Graham McQuarrie, spokesman for the National Grid, confirmed that the company had been helping police with their investigations.

He said: "The police contacted us yesterday afternoon after the discovery of a body close to one of our pylons in Botley Road, Oxford.

"When something like this happens, we go out to make sure it has not had any effect on our systems and I can confirm it did not.

"I cannot comment on any aspect of the police investigation."