Matthew Reynolds, 18, was gunned down at a house party in Winnipeg's Elmwood neighbourhood early Saturday morning. (Facebook)

Two guests who were kicked out of an Elmwood-area house party this weekend returned with friends and shot three people, two of them fatally, Winnipeg police said on Sunday.

More details of the investigation into Saturday's shooting deaths were revealed by investigators, who said three teens and an 18-year-old man have been arrested and charged with second-degree murder and attempted murder.

Matthew Reynolds and Tyler Hawula, both 18, were shot and killed with a large-calibre firearm at a home in the 400 block of Martin Avenue just after midnight Saturday. A 17-year-old boy was also wounded and is recovering in hospital.

A shotgun was recovered by police not far from the home.

Const. Jason Michalyshen said homicide investigators have learned that two youths aged 16 and 17 were guests at the party earlier on Friday night but were asked to leave after a dispute. They were escorted out of the home, police said.

Michalyshen said the teens returned later with two friends, aged 16 and 18, and were armed with a gun. They allegedly entered the home and fired, striking the three victims.

The suspects then fled, police said. Efforts by forensic investigators and the homicide squad led to their arrests, Michalyshen said.

Police said one of the 16-year-olds allegedly pulled the trigger, but all four suspects were charged because of their alleged participation and knowledge of what was going to happen, Michalyshen said.

While one of the suspects is affiliated with a Winnipeg street gang, police don't believe the shooting was gang-motivated, Michalyshen said.

While police did not identify all the suspects because of Canadian youth justice laws, they identified the 18-year-old man charged with the killings as Cody Ronald Delorme.

All four suspects are in police custody and will make a first court appearance on Monday.