The man connected to the rental of the Tesla Cybertruck that exploded outside of a Trump Hotel in Las Vegas on Wednesday is a US Special Forces soldier assigned to the 10th Special Forces Group, according to four US officials.

The man, who has not been identified publicly, is a US Army special forces operations sergeant and holds the rank of master sergeant, which is a senior enlisted rank, the officials told CNN. He was on active duty but was on leave from Germany, where he had been serving with the 10th Group, at the time of the incident, three officials said.

The driver of the Cybertruck was killed and seven others nearby were injured on New Year’s Day when a combination of fireworks, gas tanks and camping fuel in the bed of the vehicle were detonated by a device controlled by the driver, police said.

The explosion could have been significantly worse if not for the vehicle’s body construction, which helped contain the blast, police said.

The FBI in Denver, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Colorado Springs Police Department are conducting “law enforcement activity” at a home in Colorado Springs related to the explosion, the FBI said.