MANILA (REUTERS) - A 90-year-old Philippine senator, a hero of the 1986 People Power uprising that ousted dictator Ferdinand Marcos, surrendered to authorities on Friday after an anti-graft court ordered his arrest for the misuse of congressional funds.

Juan Ponce Enrile will undergo trial for pocketing 172 million pesos (S$4.9 million) from a congressional fund known as the "pork barrel" from 2006 to 2010. The fund was abolished last year by President Benigno Aquino as part of his efforts to tackle corruption.

Enrile was the third senator arrested on plunder charges. The court denied his petition to be freed on bail due to his old age and poor health.

"He is ready, willing and able to face the charges against him and he wants to do that to clear his name and his family,"said Jack Enrile, the senator's son and a former congressman.

Prosecutors said Enrile had diverted congressional funds to bogus non-government organisations for agricutural projects. The money was then ploughed back to him, bureaucrats and a businesswoman who devised the scheme, prosecutors added, based on government audit reports and testimony from whistleblowers.

Two other opposition senators are on trial for plunder and in police detention. Popular action move hero-turned senator Ramon "Bong" Revilla and Jose "Jinggoy" Estrada, son of former president and now Manila mayor, have said the cases against them are politically motivated.

In 1986 Enrile, then a defence minister under Marcos, teamed up with General Fidel Ramos to spark a civilian-backed military revolt to topple Marcos.