Calgary police are searching for a suspect after a teenager was stabbed in a random attack at a dog park.

Police said officers responded to a report of a stabbing at 7:55 p.m. Saturday near 14th Street and 110th Avenue S.W.

The 15-year-old was walking with his mother in an off-leash dog park in Braeside, police said.

The pair encountered a man they did not know, police said, at which point an altercation took place and the teen was stabbed.

He was transported to hospital in non-life-threatening condition but has serious internal injuries, police said.

The whole situation is concerning for us. - Staff Sgt. Jeff MacQueen

"There was no interaction between the victims and the offender prior to this, there were no threats, there was no demand for money or anything prior to this happening," said Staff Sgt. Jeff MacQueen.

He said police are still trying to determine the motive for the attack.

"The whole situation is concerning for us … it's concerning anytime this level of violence happens," MacQueen said.

MacQueen said he understands the attack may be concerning to people who live in the area or frequent the dog park but said there's no evidence to indicate the public is at risk.

"Calgary's still relatively safe in any area but it's important to pay attention to your whereabouts, your surroundings, in any area … certainly walking your dog should be something you can still do," he said.

On Sunday afternoon, the off-leash park was filled with Calgarians and their dogs.

"I have three sons so just thinking of walking with my son and having someone accost him. My first instinct would have been to run after the person, which would have been the wrong thing to do," said Moira Botham, who said she walks her dog in the park nearly every day. "I can't imagine how the mom would have felt."

The attacker is described as a man between 40 and 50-years-old, who was wearing dark clothing and a three-quarter length jacket with reflective markings.

He fled on foot across a nearby pedestrian bridge, MacQueen said.

MacQueen asked people who live in the area to check their doorbell cameras for footage of anyone who might match that description from Saturday evening.

Anyone with information is being asked to contact police at 403-266-1234.