A four-meter (13-foot) African rock python which strangled two young Canadian boys as they slept has been euthanized, police said on Tuesday, as authorities examined what happened and why the snake - illegal in the province of New Brunswick - attacked.
Noah and Connor Barthe, aged 4 and 6, died early Monday after the 45-kg (100 lbs) snake escaped from its glass cage through a ventilation shaft, slithered through ductwork and crashed through the ceiling into the room where they were sleeping.
Police have launched a criminal investigation into the two deaths, which prompted headlines in Canada and beyond and sparked questions about rules on keeping exotic pets.
"It's a criminal investigation because two young boys lost their lives," Alain Tremblay, a sergeant with the Royal Canadian Mounted Police, told a news conference.
He said it would take time to gather evidence to present to a prosecutor.
The boys were at a sleepover at the apartment, above the Reptile Ocean exotic pet store in Campbellton, a city of about 7,500 in Canada's maritime province of New Brunswick.
Initial reports said the snake escaped from the store into the residence, but police said on Tuesday it was being held in a glass enclosure in the same apartment as the two children.
"(The enclosure) went right up to the ceiling, but inside there was a small hole that was connected to the ventilation system," said Tremblay.
Police did not address the legality of keeping the python in a private residence. But a provincial spokeswoman confirmed that the African rock python is not a permitted species in New Brunswick.
In a brief statement carried live on Canadian television, Dave Rose, the boys' great uncle, appealed for privacy to give the family time to mourn.
"They were two typical children. They enjoyed life to the maximum," he said, his voice breaking with emotion.
Police said autopsies were being performed on both the boys, who Rose said had spent the day before they died at a garden barbecue and then playing at a family farm.
One expert said African rock pythons do not normally view humans as food, adding that the snake must have been confused when it encountered the boys.
"A defensive attack, it would just be strike and release. They normally don't constrict what they're not going to eat," said Bry Loyst, curator of the Indian River Reptile Zoo near Peterborough, Ontario, which has an African rock python on display.
The attack highlighted the lack of regulations governing exotic animals in private zoos and residences in most regions of Canada, he said.
"Potentially dangerous animals of any kind - whether it be tigers, lions, bears, cobras, rattlesnakes, large pythons - shouldn't be kept in a private residence. How do you do that?," Loyst asked.
While the circumstances of this attack were unusually shocking, python encounters have become somewhat common in North America, particularly in Florida, where exotic snakes abandoned in the wild have flourished in the near-tropical climate.
Officials in the state have estimated the population of Burmese pythons in the state as high as 150,000, and held a month-long hunt earlier this year to try to reduce that number.