Nasir al-Wuhayshi's group, al-Qaeda in the Arabian Peninsula, is behind several plots against the US, including an attempt to blow up a US commercial airliner on Christmas Day 2009.
US officials told The Washington Post they were reviewing intelligence linked to a June 9 drone strike that targeted Wuhayshi, who was also named al-Qaeda's number two, and other AQAP operatives.
"We are looking to confirm his death," a US intelligence official told the newspaper.
"There are currently four bodies belonging to al-Qaeda members. One of them is believed to be Wuhayshi's," the local official told AFP, requesting anonymity.
"The hospital remains tightlipped about the identities, but there is information from within the hospital that the body of Wuhayshi is in the morgue," he added.
CNN, meanwhile, cited two Yemeni national security officials as saying Wuhayshi had been killed on Friday.
The US government had offered a USD 10 million reward for any information leading to his capture or killing.
A former aide to al-Qaeda's late founder Osama bin Laden, Wuhayshi attended the group's al-Farouk training camp in Afghanistan in the late 1990s.
He is said to have fled Afghanistan in 2002 to Iran, where he was arrested and handed over to Yemen. There he was held without charge until he escaped by tunnelling his way out with 22 other prisoners in February 2006.
When bin Laden was killed by US commandos in May 2011 in Pakistan, Wuhayshi warned the Americans not to fool themselves that the fight would end with the al-Qaeda chief's demise.
