Defense Secretary Ash Carter says no attack will affect U.S. resolve to accelerate the defeat of the Islamic State group.

Carter is testifying Tuesday before the House Armed Services Committee just hours after explosions in Brussels that killed more than 30 people.

He says the attacks in Brussels are a reminder of the importance of dealing a "lasting defeat" to the Islamic State group.

Belgian authorities said at least 20 people have died and 106 people were injured in the attack on the Maelbeek subway station. Earlier, another top Belgian official said 11 people were killed and 81 have wounded in twin explosions at the Brussels airport.