Russia acknowledged Thursday that five of its citizens may have been killed by a U.S. strike in Syria.
Israel's air strikes marked its most serious engagement in Syria since fighting there began in 2011.
The officers said Saturday the U.S. forces had thought the victims were militants.
The United States has stepped up its operations in Somalia in recent weeks, with frequent strikes against al-Shabab.
A Taliban shadow governor who had planned attacks on Marines and Afghan soldiers for years was killed in an airstrike.
U.S. Central Command did not give any details on when and where the ground attacks were carried out.
The strike against al-Shabab militants near the coastal city Kismayo also destroyed a vehicle.
The U.S. Africa Command said the strike was carried out Friday night, about 20 miles north of Mogadishu, the Somali capital.
The U.S. Africa Command said two drone strikes killed "several terrorists" in northeastern Somalia.
The U.S. has stepped up military involvement in Somalia, carrying out at least 19 drone strikes against al-Shabab since Janua...