JAKARTA, Nov 4 (AFP) - Indonesian police have released two anti-graft investigators after wiretap recordings allegedly exposing a high-level conspiracy against the country's corruption watchdog were played in court.

Corruption Eradication Commission (KPK) deputy chairmen Chandra Hamzah and Bibit Samad Riyanto were released late Tuesday, six days after being arrested on suspicion of extortion and abuse of power, police said.

"For the sake of the larger interest and not because of any pressure, the police have decided their detention orders should be temporarily lifted," police spokesman Nanan Soekarna told a press conference late Tuesday.

"But it doesn't mean they're free because freedom requires the certainty of the law. The court will determine right or wrong, not the police."

The move will be seen as an embarrassing cave-in by the police in the face of mounting public anger over what many Indonesians see as a plot to muzzle the KPK by targeting its senior officials with bogus criminal charges.

"This is an extraordinary gift," Riyanto was quoted as saying by the Detikcom news website after his release.

"Our battle is still far from over, we will continue to fight corruption."

Their release came hours after the Constitutional Court heard secret KPK recordings of police, prosecutors and the brother of a corruption suspect allegedly discussing ways to bring false charges against the two officials.

The proceedings were broadcast live across the archipelago and fueled a second day of Jakarta street protests in support of the KPK, which is seen as one of the only clean institutions in the country.

In a further about-face for the police, Soekarna said Anggodo Widjojo, the brother of the fugitive businessman Anggoro Widjojo, had been detained for questioning.

One of the senior police officers at the heart of the alleged plot would also be questioned by a presidential "fact-finding team", he said.

The scandal has become a major test for President Susilo Bambang Yudhoyono's new coalition government, formed last month after he won a landslide election victory on the back of promises to stamp out widespread corruption.