The attack took place as al Qaeda in the Arabian Peninsula (AQAP) recruits queued for dinner at the camp, west of the port city of Mukalla on Yemen's south coast, as reported by Reuters.
The Pentagon said on Tuesday that a U.S. air strike on an AQAP training camp had killed dozens of fighters but it gave no further details.
The Yemeni sources said that at least 50 people were killed and 30 wounded. The air strikes set off huge fires inside the camp, residents said.
"The planes struck as al Qaeda people stood in line to receive their dinner meal," a local official, who asked not to be named, told Reuters by telephone.
Yemeni residents had earlier said the attack on the base was carried out by war planes from a Saudi-led coalition which over the past year had been trying to stop the Iran-allied Houthi group from completing its takeover of the country.