WASHINGTON - US warplanes on Sunday destroyed 10 armed vehicles of Islamic militants in their continued air raids near the Mosul Dam in northern Iraq.

The Central Command said a mix of fighter, bomber, attack and remotely piloted aircraft were used to conduct 14 airstrikes aimed at supporting humanitarian efforts, protecting critical infrastructure, US personnel and facilities, as well as backing up Iraqi and Kurdish forces fighting militants from the Islamic State of Iraq and the Levant (ISIL).

ISIL's 10 armed vehicles, seven Humvees, two armored personnel carriers and one checkpoint were damaged or destroyed in the attacks, the Central Command said in a statement, noting nine strikes were carried out on Saturday.

President Barack Obama on Sunday notified US Congress that he authorized the targeted strikes near Mosul Dam on Thursday to support Iraqi forces in their effort to recapture the dam, Iraq's largest.

"The failure of the Mosul Dam could threaten the lives of large numbers of civilians, endanger US personnel and facilities, including the US embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace, " he said in a letter to congressional leaders.

He said the operations that started on Friday would be "limited in their scope and duration."

Obama first authorized limited airstrikes on ISIL targets on Aug 7, as the group seized more cities and towns in its advance on Erbil, capital of Iraq's autonomous Kurdish region, and trapped many civilians including the minority Yazidis on Mount Sinjar.