WASHINGTON (AP) — President Barack Obama has sent official notification to Congress of his order for last week’s airstrikes and humanitarian aid drops to help Iraqis threatened by Islamic State militants.

The White House on Monday released a letter formally letting Congress’ leaders know that Obama approved the mission that repelled Sunni fighters in the northern Shiite town of Amirli and dropped food, water and medical supplies for civilians.

Such notifications are required by law and are considered a formality.

The Islamic State group has control of vast swaths of Syria and Iraq, has killed civilians from that region and beheaded American journalist James Foley.

The United States has conducted airstrikes in northern Iraq to halt the advance of Islamic State fighters. It is also considering extending its air campaign into Syria.

Meanwhile, the U.S. Central Command said that American military forces continued to attack Islamic militant targets, using fighter and attack aircraft to conduct three airstrikes Sunday and Monday near Mosul Dam.

It said the strikes destroyed three trucks, severely damaged another, destroyed an armed vehicle and took out a mortar position near the dam. The Central Command said all aircraft exited the strike area safely.

THE ASSOCIATED PRESS