Selkirk RCMP are asking witnesses to come forward after discovering four teenagers with stab wounds at a property on Highland Drive in the RM of St. Andrews on Friday night around 11:40 pm.

An RCMP investigation found a party at the home had an open invitation posted on social media leading to a large number of attendees.

Police said they found a 16-year-old and 17 year-old boys with stab wounds outside the home.

Officers also found a 17-year-old with stab wounds inside the home.

On Monday, police said a fourth teenage boy had also been stabbed.

All four victims were taken to hospital with minor injuries.

Police said the stabbing happened after an altercation between two groups.

A visibly shaken man identified himself as the homeowner of the house on Highland Drive where the party took place.

The man said the party was for his son's 18th birthday and he was at the party.

He said people broke his patio door before the commotion spilled out on to the street. He said he called police and asked for an ambulance.

The homeowner told CTV News Monday he had no idea how many people were invited to the party and was surprised at the number of people who showed up.

Police said officers witnessed about 200 people, mostly underage trying to leave the area on foot and vehicles.

People living nearby say young people were running all over the neighbourhood. 

"She said mom, ‘I heard screaming and freaking out. It wasn't goof screams it was screams of terror,’ and yeah the kids were hiding in backyards, behind trees,” said Corrina Rach whose daughter attended the party.

Rach said after two hours she found her daughter hiding in a ditch.

Kathy Johnston lives about 500 metres away and heard the party walking her dogs.

"It sounded quite loud. Lots of guys. Sounded like they were chanting almost like a soccer game," she said.

Police believe there are five suspects who were travelling in a small red hatchback, possibly from Winnipeg.

Selkirk RCMP are asking anyone who may have witnessed, taken videos or photos of the fisticuffs to contact them at 204-482-1222.

POLICE RESPONSE TIME

One neighbour said he heard angry screams and a young man in his yard told him to call police because, “there's weapons”.

The neighbour said he called 911 and was transferred to Selkrik RCMP and got a busy signal for about five minutes, before he was told police were on the way.

"All of a sudden 50 of them start phoning. Someone is not getting through that's what 911 is for. RCMP did get these calls and responded immediately," said Sgt. Paul Manaigre.

He said police received the first call about the party at 11:42 p.m., and the first officers arrived on scene at 11:59 p.m. - 17 minutes later.

The call was just two minutes apart from an unrelated call about a 15-year-old boy fatally hit on his bicycle.