WASHINGTON - An apparent U.S. missile strike along Pakistan's border with Afghanistan is believed to have killed a top al-Qaeda operations planner last week, U.S. counterterrorism officials said Friday. If confirmed, this would be the second deadly attack against a senior terrorist leader this fall.

Saleh al-Somali was one of two Arab men thought to have been killed when a pair of missiles tore into their car Tuesday near the town of Miran Shah in North Waziristan province, according to U.S. sources and Pakistani officials in the region. Local authorities said the missiles were fired by an unmanned aircraft of the type operated by the CIA inside Pakistan's lawless tribal belt.

"They were driving in a white car, heading toward the Afghan border, when the car was hit," said an official with Pakistan's civilian intelligence agency, speaking by phone from Miran Shah. The official said local militants rushed to the spot and quickly confiscated what remained of the "totally demolished bodies."

Local authorities were unable to verify the victims' identities, but two U.S. counterterrorism officials cited unspecified evidence that Somali was among the dead. Somali was described as a senior al-Qaeda military planner who ran the terrorist group's operations outside the Afghanistan-Pakistan region.

"He was engaged in plotting throughout the world," said a senior official who spoke on condition of anonymity, citing the sensitive nature of U.S. air strikes inside Pakistan.

If his death is confirmed, Somali would be the second senior al-Qaeda or Taliban leader killed since September, when a strike killed Najmuddin Jalolov, head of a militant faction in the tribal belt, and three other operatives.