The Canadian Mounties were confronted with a particularly gruesome case on Tuesday, two small boys killed in their sleep apparently by an African python.

The boys -- brothers aged five and seven -- were sleeping at a friend's apartment on Sunday in the small town of Campbellton in the east of the country when they were surprised by the snake.

Police believe the python slithered out of its enclosure in a pet store and got into the ventilation system through a grille that opened directly into the beast's terrarium.

From there it slithered upstairs to an apartment owned by the pet store's manager, dropped through a broken pipe and -- police believe -- choked the children.

Sergeant Alain Tremblay, of the Royal Canadian Mountain Police, identified the brothers as Noah and Connor Barthe.

"The apartment is located upstairs from a reptile store where the snake had gotten out of his enclosure, made his way into the ventilation system," he said.

"Then into the living room where the two boys were sleeping," he said.

Autopsies were expected Tuesday but at this stage it is believed the boys were strangled by the snake, which is of a species that constricts its prey and squeezes out its life.

"The snake was captured and is in RCMP possession. The investigation into what happened is ongoing," Tremblay said.

Police said the snake was a rock python, also known as a python sebae, the biggest snake species in Africa. It is not poisonous, but is hugely strong and capable of killing large animals including antelopes.
It is not known as a man-eater in the wild, but it is widely feared.

Canadian media said the snake was four meters (13 feet) long and weighed around 45 kilos (100 pounds).

The boys' great uncle, Dave Rose, appealed for the media to respect the family's privacy, and described their final hours with emotion.

The family had been guests of the pet store owner, Jean-Claude Savoie, and his young son, and had spent the day playing in a paddling pool, eating barbecue and riding a tractor.

"So, a super day," he said. "And then after a long day late into the night, they got home for the sleepover and the two families stayed together until midnight."

The brothers stayed on with their young friend for a sleepover above the pet shop, and Savoie said he found the boys' bodies Monday morning.

"I have many mixed emotions right now. It's ridiculous. I can't believe this is real," he told Radio-Canada.

"It's strange, I'm just trying to piece it together," added Lee Parker, the facilities manager at an Ontario reptile zoo named Reptilia.

He told CBC that pythons only kill to eat.

"They don't go on killing sprees ... it doesn't make sense to me," he said.

Former pet shop owner Laurent Brisson told Radio-Canada that heat can also attract such snakes and that hunting is simply a matter of instinct.

The RCMP major crimes section is carrying out a criminal investigation but has not brought charges.

The incident sparked strong reactions in Campbellton, a town of just over 7,000 people on Chaleur Bay in northern New Brunswick.

Deputy Mayor Ian Comeau expressed sorrow over the accident and noted that there had been opposition to the presence of the exotic pet store in the town.

He pledged the city ordinance that allowed it would immediately come under review.