SUDBURY -- Greater Sudbury Police said Thursday they are certain there are more people involved in setting a deadly fire in a Sudbury Housing complex on Bruce Avenue on April 11.

This week, investigators arrested 25-year-old Liam Stinson of Sudbury. He faces several charges in connection to the incident, including conspiracy to commit murder.

"There are more people that we know that are involved," said Insp. Det. John Valtonen of the Greater Sudbury Police Service. "We know for a fact that is the case and that's why we are continuing with the investigation. It's a very live, active investigation."

Two women and a man were killed in the blaze, which police confirm was deliberately set. A 37-year-old man who jumped from a second-story window is in stable condition.

"To those who are responsible, we know there is a story, we know that there is a reason for why things worked out the way they did," said Valtonen. "We are just going to be relentless to find out who you are."

Police are appealing to anyone who took video in the area of the fire to contact them. Even if they think there's nothing relevant to the case on their recording, he's hoping people will come forward.

"You just never know," said Valtonen.

Police said information from the public is helping them piece the puzzle together to explain exactly what happened that fateful night.

"We are continuing to talk to people, people are reaching out to us, but it's important that if you are wondering whether or not you might know something and someone else will say it, we ask, please come forward," said Valtonen.

Crime Stoppers is offering an $2,000 reward for tips received by April 30 for information that leads to the identity of other people involved in this triple murder, attempted murder and arson.