An off-duty Border Patrol agent confronted a man at a Riverside County home early Saturday and fatally shot him, but was later arrested, authorities said.

The officer suspected of the shooting is 40-year-old Hemet resident John Demery, according to the Riverside County Sheriff's Office.

Sheriff's deputies were dispatched at 12:47 a.m. to the 41100 block of Toledo Drive in East Hemet on what initially was an assault call, but when they pulled up to the home they found the victim suffering from multiple gunshot wounds, Riverside County sheriff's Deputy Patty Stoyer said.

The victim, identified as Adam Thomas, 27, of Moreno Valley, was taken to a hospital where he was pronounced dead, Stoyer said.

Sheriff's deputies arrested suspect Demery in connection with the shooting. He was booked on suspicion of murder and remained in jail on $1 million bail, records showed.

The Department of Homeland Security placed an agent from its Murrieta station on administrative leave after their involvement in the shooting, according to a statement released later in the day.

The release did not identify Demery by name, but referred to the Riverside sheriff's investigation into the Hemet shooting.

"U.S. Customs and Border Protection’s Office of Internal Affairs and the U.S. Border Patrol’s San Diego Sector are cooperating with the Riverside Sheriff’s Office, who is leading the investigation," the release said.

City News Service contributed to this report.