Military officials said at least 15 people were killed in the dawn strike on a militant camp on remote southern Jolo Island, including two other high-level leaders. A national military spokesman, Col. Marcelo Burgos, initially reported that Marwan was among them.

Marwan’s death would mark a major success in disrupting the Jemaah Islamiyah terror network blamed for some of the most spectacular bombing attacks in Southeast Asia in recent years. But if the initial report proves incorrect, it would turn a largely successful strike into a partial embarrassment for the Philippine military, while burnishing the reputation of the elusive terrorist.

The U.S. has offered a $5 million reward for the capture of Marwan, a U.S.-trained engineer accused of involvement in deadly bombings in the Philippines and in training militants.

Cabangbang said the announcement of Marwan’s killing was based on information provided by informants. He refused to elaborate, saying it would compromise intelligence assets.

“We are still searching. Our troops are still there,” Cabangbang said.

He suggested that the blast could have obliterated Marwan’s body, saying the process of verification linked to the possible disbursement of the reward money to informants will be “more tedious” and could include DNA testing.

Two Philippine security officials with knowledge of the airstrike who spoke to The Associated Press also said Marwan’s body was not found, though bombs shattered the house where he was believed to have been.

One of the officials confirmed the deaths of the other two high-level leaders: Umbra Jumdail, who led the Philippine-based Abu Sayyaf militant group, and a Singaporean leader in Jemaah Islamiyah, Abdullah Ali, who used the guerrilla name Muawiyah. The other official confirmed only the death of Jumdail, also known as Dr. Abu Pula, and his son.

Both officials spoke on condition of anonymity because they were not authorized to talk to reporters.

Cabangbang said the decision to announce the killings, including that of Marwan, was made by the chief of staff of the Armed Forces of the Philippines, Gen. Jessie Dellosa, after he was briefed by commanders.

“There are details that we cannot divulge because of operational security,” he said when pressed for details.

A U.S. official in Washington confirmed the strike on Jolo Island, an impoverished region 600 miles (950 kilometers) south of Manila, and said the Pentagon provided assistance in one of the region’s most successful anti-terror operations in years. The strike debilitated a regional militant network that has relied on the restive southern Philippines — sometimes called Southeast Asia’s Afghanistan — as a headquarters for planning bombings and a base for training and recruitment