24 U.S. troops die on one of deadliest days in Iraq

Attacks in Iraq and the crash of a Black Hawk helicopter brought to 24 the number of American troops killed in Iraq on Saturday, making it one of the deadliest days for the U.S. military since the war began almost four years ago.

The U.S. military is investigating the cause of the helicopter crash northeast of Baghdad that killed 12 soldiers.

However, a senior military officer said the initial indications point to hostile fire as the cause of the crash.