Mr Anwar was sacked by Prime Minister Mahathir Mohamad in 1998
Police in Malaysia say they are investigating renewed sodomy allegations against the opposition leader, Anwar Ibrahim.
A 23-year-old aide to Mr Anwar is said to have filed the complaint.
Mr Anwar has denied the claim, saying it is designed to block his political resurgence after success at the polls.
The ex-deputy PM was jailed in 1998 on sodomy and corruption charges he has said were politically motivated. The sodomy conviction was later overturned.
Although freed from jail in 2004, the corruption conviction barred him from holding political office until 15 April 2008.
The latest claims against him came from a 23-year-old man who has worked alongside him from the beginning of the year.
Mr Anwar said they were "a complete fabrication".
In a written statement he said: "I believe we are witnessing a repeat of the methods used against me in 1998 when false allegations were made under duress."
One of his senior aides told the BBC: "This is a photocopy of the script from 10 years ago."
A party spokesman said Mr Anwar had been moved to a foreign embassy in the capital Kuala Lumpur for his own safety.
Mr Anwar, 60, said the sodomy claim was aimed at stopping the opposition from gaining further ground.
"This is clearly a desperate attempt by the... regime to arrest the movement of the Malaysian people towards freedom, democracy and justice," he said.
The right moment
But Prime Minister Abdullah Badawi denied that the government had fabricated a case against him.
There was no conspiracy "to cause [Anwar] trouble or harass him or raise such issues to undermine him", he said.
In the general election in March, Mr Anwar led an opposition alliance to considerable gains.
They won control of the legislatures in five out of the country's 13 states, and an unprecedented 82 of the 222 seats in the House of Representatives.
The ruling National Front saw its worst showing in decades, prompting calls for Prime Minister Abdullah Ahmad Badawi to resign.
Since then Mr Anwar has said he has the support of enough MPs to topple the government but is waiting for the right moment.