Ottawa police are searching for a suspect after a man attempting to break up a dispute was stabbed in downtown Ottawa.

The suspect, identified as 21-year-old Jaycob Mainville, is considered armed and dangerous.

The stabbing happened at Rideau Street and Mackenzie Avenue Thursday morning, police said. The victim was transported to hospital with serious but non-life-threatening injuries.

Police say a man and a woman were involved in an altercation at approximately 10 a.m. Thursday when a third person observed the dispute and attempted to separate the two people.

"The suspect involved in the dispute proceeded to stab the man," police said in a statement.

Police say while the stabbing was an isolated incident, the suspect is considered armed and dangerous.

Witnesses say the stabbing in the popular tourist area is concerning.

"It's not something you would usually see, or think you would see in this area," said Reid Gauthier.

"I saw like six cop cars and someone passed out and a crowd around them, I figured it was someone that had OD'd," said Victoria Schorr. "I didn't know why they needed so many cops."

Anyone with information on Mainville is asked to contact the Ottawa Police Central Investigations Unit at 613-236-1222, ext. 5166.

The Fairmont Chateau Laurier hotel is at the northwest corner of Rideau and Mackenzie, with the Senate building in the former train station on the south side of the intersection.

MacKenzie Avenue was closed at Rideau Street, along with the westbound lanes of Rideau. The roads have since reopened.

With files from CTV News Ottawa's Jeremie Charron