Evidence suggests the pair may have been accidentally poisoned while holidaying in Thailand.
Thai police confirmed Sunday that the women didn't appear to have been murdered and their belongings hadn't been taken when they were found in their hotel room. An analysis of their stomach contents will help determine the cause of death, they said.
Noemi Belanger, 26, and her sister Audrey Belanger, 20, were found Friday at the Phi Phi Palm Residence Hotel on Phi Phi Island, said police Lt. Col. Jongrak Pimthong.
The pair grew up Pohenegamook, a town in eastern Quebec near the Maine border. They studied in Quebec City with their eldest sister, but worked at the family store in the community of roughly 3,000.
The town's mayor, Louise Labonte, who taught the sisters in high school, described them as adventurous and full of promise.
"We lost two brilliant young women," she said Sunday. "It's of course very difficult for the family, and everyone here."
Messages posted on Noemi Belanger’s Facebook page earlier wished the young woman and her sister a great trip. By the weekend, the page had been transformed into a makeshift memorial.
"My condolences to the entire Belanger family," read one post. "We're wholeheartedly with you."
Jongrak said police couldn't yet conclude the cause of death, adding the most important evidence would be an analysis of the contents of the victims’ stomachs. He said the bodies were found Friday by a hotel maid.
“Police determined they were dead for about 24 hours prior to that and only found a lot of vomit in the room,” he said. The vomit, along with traces of blood on the women’s face, could be signs of a toxic reaction, police said.
“There was neither signs of fighting, nor robbery, but we found many kinds of over-the-counter drugs, including ibuprofen, which can cause serious effects on the stomach,” he said, after a team of investigators combed through the hotel room on Sunday.
The bodies would be sent to the Central Forensic Institute in Bangkok for further examination, rather than a regional hospital as originally planned, he said.
Foreign Affairs spokesman John Babcock confirmed that two Canadian citizens had died in Thailand, but did not provide further details. He said Canadian consular officials in Bangkok were providing assistance to the family and were in contact with local authorities.
Tourists’ deaths are not uncommon in Thailand, which saw about 19 million foreigners visit last year. The causes range from road accidents to foul play and drug overdoses.
Thai police said the hotel where the women checked in on Tuesday was located in an upscale area of the island, which is known for partying and as the location where the movie “The Beach” starring Leonardo DiCaprio was filmed.
Thai media earlier quoted another officer, police Lt. Siwa Saneha, as saying the two women went out to socialize on the night of their arrival. He said a hotel maid came to clean their room on Wednesday and Thursday, but did not enter because she believed they were inside.
On Friday, “the maid wanted to check if they wanted to stay at the hotel for another night but didn’t hear any response, so the hotel used a spare key to access the room,” said Jongrak.
Jongrak recalled a similar incident on Phi Phi Island in May 2009 when two women from the United States and Norway died after suddenly falling ill at a guesthouse, but refused to comment if the two cases shared the same cause of death.
In that case, the victims suffered severe vomiting and stomach pains before being rushed to hospital. Doctors determined the proximate cause of death as dehydration and shock, but it was not known what caused their sudden illness. Two other people with the same symptoms survived.
Another spate of mysterious tourist deaths occurred last year in the northern Thai city of Chiang Mai, involving several visitors from different countries staying at the same hotel in January and February.
The cause of death was not established, though some evidence suggested the use of the chemical spray chlorpyrifos, used to kill bedbugs, may have been responsible.
— with files from the Associated Press.