"They found the body of a male on Harrowdown Hill," five miles from Kelly's home in Abingdon, a police spokeswoman told a press conference.

Kelly, 59, has been fingered as the possible source behind a BBC report which alleged the British government had "sexed up" its dossier on Baghdad's arms capabilities ahead of the war on Iraq.

Kelly disappeared on Thursday afternoon, two days after facing a grilling by a parliamentary committee investigating the affair.

He had denied being the main source for BBC reporter, Andrew Gilligan's, allegation that the government had altered the weapons dossier, and reportedly alluded during questioning to the intense pressure he was under amid the fierce media interest in the affair.

"We are obviously very concerned about the welfare of Dr Kelly and hope that he returns safely," a Downing Street spokesman said after learning of the expert's disappearance. Kelly left his house on Thursday telling his wife he was going for a walk, and never came back.

The identity of the body would not be determined for a couple of hours, Thames Valley police spokeswoman Victoria Bartlett told AFP Friday morning.

In his BBC radio report in May, Gilligan claimed Alastair Campbell, the government's director of communications and key aide to British Prime Minister Tony Blair, had ordered that the claim that Iraq could deploy chemical or biological weapons in as little as 45 minutes, be inserted into a government dossier released in September.

The report sparked a furious row with the government, prompting the official parliamentary inquiry into the intelligence presented by Downing Street as a justification for joining the US-led war on Iraq in March.

WAR.WIRE