ISLAMABAD, Pakistan — One of Pakistan’s most wanted militant commanders, Ilyas Kashmiri, was killed in an American drone strike in the tribal territory of South Waziristan, residents and a militant active in the area said Saturday. But Pakistani and American officials cautioned that they had not been able to confirm his death.

Mr. Kashmiri is considered one of the most dangerous and highly trained Pakistani militants allied with Al Qaeda. A former member of Pakistan’s special forces, the Special Services Group, Mr. Kashmiri was suspected of being behind several attacks, including the May 22 battle at the Mehran naval base in the southern port city of Karachi that deeply embarrassed Pakistani officials. He has also been implicated in the terrorist attack on Mumbai, India, in 2008, in which at least 163 people were killed, including some American citizens.

He was reported to have been killed Friday in a strike on a compound in Laman, near Wana, the main town of South Waziristan. Atifur Rehman, a senior government official in Wana, said the strike killed nine people. Mr. Rehman said there had been reports that Mr. Kashmiri had recently set up operations in Laman, and that a sharp increase in drone flights over the area had been noticed in the past few days.

A known Taliban militant in Wana contacted by telephone confirmed that Mr. Kashmiri had been killed. But an intelligence official in the capital, Islamabad, speaking on condition of anonymity, said he had not received any independent confirmations of the report. And American officials — who cautioned that previous reports of Mr. Kashmiri’s death had turned out to be false, including a Pakistani claim he had died in a drone strike in September 2009 — said they were trying to confirm the new reports on Saturday morning.