Police have charged two men with murder in the stabbing death of an 18-year-old man on the weekend.

Lukas Strasser-Hird

Lukas Strasser-Hird died on Nov. 23, 2013, after he was assaulted outside a downtown bar. (Facebook)

Lukas Strasser-Hird died on Saturday morning after he was involved in two altercations outside a downtown bar, police said.

“Many of the same people involved in the second incident were involved in the front incident," said homicide unit Staff Sgt. Tom Barrow.

"There was a separation of the two groups. The victim and his associates were removed from the first location and were escorted through the bar and released into the back alley of the bar. The two groups then met up again, perhaps even by coincidence."

When emergency crews found him in the alley behind 10th Avenue and Second Street S.W. around 2:45 a.m. MT the victim had critical, life-threatening injuries.

He later died in hospital.

An 18-year-old man has now been charged with first-degree murder and a 19-year-old man with second-degree murder, police said on Monday.

Both men were scheduled to make court appearances on Monday.

Detectives believe other people might have been involved in the deadly assault.

An autopsy is scheduled for Tuesday.