It was the biggest reward given so far by Washington in the campaign to wipe out al-Qaida-linked militants in the southern Philippines, where the US military has been training and advising Filipino troops.

The embassy added that it is the largest Rewards for Justice payment in the Philippines since the program began in 2002.

Among the suspected terrorists in the Rewards for Justice program are Jemaah Islamiyah members Dulmatin with a $ 10-million reward, Umar Patek, $ 1 million; and Zulkifli bin Hir, also known as "Marwan," $ 5 million.

Of the three JI members, Dulmatin and Marwan are in the Office of Foreign Asset Control List by the US Department of Treasury. The Office of Foreign Asset Control List prohibits individuals and corporations from providing financial or material support to designated individuals.

The US promised a reward of up to $ 5 million each for Abu Sayyaf Group chief Khadaffy Janjalani, who was slain in a September clash in Jolo, Sulu, and his presumed successor, Abu Sulaiman, who was killed in Jolo last January.

"Information provided by the brave Filipino citizens recognized today was instrumental in assisting the Armed Forces of the Philippines to track down and locate these two terrorist leaders," the embassy said in a statement.

The four men, wearing masks to protect their identities, received the money in five black plastic suitcases at the Sulu provincial capitol complex in Jolo from embassy officials. Kenney and Armed Forces of the Philippines Chief of Staff Gen. Hermogenes Esperon witnessed the payment.

More than 7,000 Filipino soldiers, backed by US military surveillance and other non-combatant assistance, have been waging an offensive in Jolo since last August.

Authorities have declined to discuss the precise role of the informats and how their information contributed to the slayings of the two terror suspects, citing concerns for their safety.

Philippine officials have said the four informants included former Abu Sayyaf members who surrendered to the military and, last January, led troops to a jungle grave where the decomposing remains believed to be of Janjalani were found buried. (with reports from AP)