A man accused of murder was arrested on Wednesday morning following a two-hour standoff with law enforcement in Greeley, according to the Greeley Police Department.

On Wednesday morning, officers learned 28-year-old Kyle Moore was at a home in the 2400 block of A Street. Moore had an outstanding warrant for murder after a shooting killed Victor Martinez, 51, on Dec. 14, according to a release from the department.

The department’s SWAT Team along with other members of the department responded to the home at 9 a.m. to arrest Moore. When authorities arrived, multiple unrelated parties left the home and surrendered to officers, but Moore stayed inside.

Police sent out a reverse 911 to nearby residents and urged them to shelter in place.

After two-hours, authorities used several chemical munition agents, which forced Moore to surrender to authorities without incident. He was treated for chemical gas exposure before being taken to the Weld County Jail.

On Tuesday, Moore’s alleged accomplice, Trent O’Neil, 22, was arrested in Thornton. Both men are being held on suspicion of murder and aggravated robbery, police said.