US readies retaliatory strikes for drone attack by Iran-backed militants

Officials said they would play out "over the course of several days."

The U.S. response to a drone attack that killed three American service members in Jordan last weekend will be carried out "over the course of several days" and striking "multiple targets," a U.S. official told ABC News Tuesday.

"These are going to be very deliberate targets -- deliberate strikes on facilities that enabled these attacks" on U.S. forces, said the official, speaking on condition of anonymity in order to discuss sensitive details.

Officials would not say whether any of the targets would be inside or outside Iran.

Leaving the White House Tuesday morning, President Joe Biden said he had decided how the U.S. would respond to the attack by Iran-backed militants, but gave no more details.

When asked if Iran is responsible, he said Tehran is arming these proxy groups. "I do hold them responsible in that they're supplying the weapons to the people who did it," he said.