A man who stabbed the manager of an Adams County Family Dollar Store to death over an argument at the shop has been convicted of first-degree murder nearly a decade after the crime, according to a news release from the 17th Judicial District Attorney’s Office.

Anthony Dennis Grayson, 51, was convicted of first-degree murder by an Adams County jury after a four-day trial. Grayson faces a mandatory sentence of life in prison without the possibility of parole, the news release said.

The case faced delays because of issues around the defendant’s competency, the news release said, but Grayson was found competent and chose to represent himself at trial.

In September 2016, the Adams County Sheriff’s Office responded to a stabbing at the Family Dollar Store, 7067 Pecos St. Surveillance video and witnesses revealed that Grayson confronted manager Alejandro Alvear inside the store, the news release said. After an exchange, Grayson pulled a knife and stabbed Alvear several times. Alvear was taken to Denver Health Medical Center, but he did not survive.

Witnesses said Grayson demanded money back from Alvear and threatened to stab him if he refused, the news release said. The incident was caught on a security camera. Grayson was taken into custody at the scene and later charged.