A St. Louis gas station clerk facing a murder charge in the fatal shooting of a customer he believed tried to steal candy has pleaded guilty to a related federal gun charge.

The U.S. attorney's office announced Monday that 40-year-old Taleb Jawher admitted to being in possession of a firearm while in the country illegally, which carries up to a 10-year sentence. Immigration officials say Jawher, who is originally from Jordan, came to the U.S. legally but overstayed his visa.

He's awaiting trial on first-degree murder and armed criminal action charges in the September killing of 34-year-old Christopher Simmons outside a Phillips 66 gas station. Police allege Jawher wrongly accused Simmons of trying to steal a $1.10 bag of candy, then followed him outside and shot him.