The U.S. government launched a mission to salvage what officials say is spy equipment from the Chinese balloon shot down off the coast of South Carolina on Saturday, as pressure mounted on U.S. President Joe Biden to hit back at Beijing over the incident with new export controls on sensitive technology.

The government anticipates finding equipment capable of taking detailed photographs, along with other sensors, one person familiar with the matter said. U.S. lawmakers are already demanding to know if the balloon’s payload contains technology from the U.S. or its allies, another person said. Both asked not to be identified because the administration doesn’t want to reveal exactly what it suspects the balloon was carrying.

The balloon, said to be the size of at least two school buses, and its sensors are lying in 15 meters (50 feet) of water and scattered over an 11-kilometer (7-mile) area off Myrtle Beach. Divers and cranes operating from the surface were expected to haul it up in the coming days, potentially giving intelligence analysts crucial insight into Chinese spying capabilities.