Jakarta - Indonesian President Susilo Bambang Yudhoyono on Friday denied he was involved in an alleged attempt to weaken the country's anti-corruption body after two of its investigators were detained by police on bribery charges.

Police on Thursday arrested Chandra Hamzah and Bibit Samad Riyanto, two of the four deputy chiefs of the Corruption Eradication Commission (KPK), charging them with abuse of power and accepting bribes while investigating a corruption case involving a businessman.

Anti-graft activists said the move was part of a conspiracy involving forces within the police and the Attorney General's Office to undermine the commission, which has the power to arrest and prosecute suspects.

Local media have published transcripts of alleged taped conversations between senior state prosecutors, police officers and the brother of the businessman subject to the commission's investigation in which they discussed an apparent plot to frame Hamzah and Riyanto.

In the transcript, one of the alleged plotters spoke of Yudhoyono's support for attempts to remove the two commissioners.

"If anyone tries to undermine KPK, I will be in the front line to defend it," Yudhoyono said at a news conference.

Yudhoyono urged police to investigate the alleged recording.

"I have no knowledge [of the alleged plot]," the president said. "I didn't make such communication."

The commission's chairman, Antasari Azhar, has been in police detention since May for his alleged involvement in a murder case.

He allegedly told investigators that his deputies accepted bribes from a businessman who is a suspect in a corruption case.

National police chief Bambang Hendarso Danuri said police had two witnesses who told investigators that Hamzah and Riyanto received bribes from the businessman.

"It is not true that there's a conspiracy," he told reporters. "Our work is accountable." But the commission's acting chairman, Tumpak Hatorangan Panggabean, has told reporters his office was in possession of a tape that indicated the alleged conspiracy.

The anti-corruption commission was created in 2003 to tackle endemic graft. It has been praised by the public for a series of successful prosecutions against legislators, former ministers, a prosecutor and central bank top officials, one of whom is an in-law of Yudhoyono. (dpa)