The US state department describes Mr Usman as a bomb-making expert
A Filipino militant wanted by the US is believed to have been killed by an American drone aircraft near the Afghan border, Pakistani officials said.
Abdul Basit Usman was reported killed on 14 January along with several others on the border of South and North Waziristan tribal regions, they said.
The US state department has offered a $1m reward for information leading to the militant's capture.
Authorities in Philippines said they were investigating the report.
"If the reports are true then it is good news for us because the killing of Basit Usman means one less terrorist on the street," the AFP news agency quoted Lt-Gen Benjamin Dolorfino, military commander in south-western Philippines, as saying.
But, he added: "We still have to verify the reports."
Mr Dolorfino said he was involved in many deadly bombings in the southern Philippines' Mindanao region, where Muslim insurgents have waged a decades-old separatist rebellion, the AFP reported.
Correspondents say that if it is confirmed, the death of Abdul Basit Usman would represent a major success for the US authorities.
The US state department describes him as a bomb-making expert with links to the Abu Sayyaf militant organisation in the Philippines.
It says he has links to Jemaah Islamiah, a South-east Asian Islamic extremist group linked to al-Qaeda.
"US authorities consider Basit to be a threat to US and Filipino citizens and interests. Basit is believed to have orchestrated several bombings that have killed, injured, and maimed many innocent civilians," the state department website says.
According to earlier report, the 14 January drone attack had targeted Pakistani Taliban leader Hakimullah Mehsud.
A Taliban spokesman said Mehsud had been in the area but left before the attack.