The anonymous correspondence renewed the hope that an investigation into the devastating arson fire could be reactivated, but Mounties in Prince Rupert, B.C., made little headway.
A member of the bereaved family spoke publicly on Thursday, the 25th anniversary of the fatal blaze, and made an emotional appeal to the secret author to reveal his or her identity.
"I am begging, pleading and hoping that this person or anyone who may have any information, big or small, regarding this arson-homicide to please contact the RCMP," Lorraine Rochon said at a news conference in Surrey, B.C., her voice cracking with emotion.
Rochon, who was one of four sisters, addressed the killer directly, saying her family would never give up its quest to get closure.
"And if you didn't intend for anyone to be hurt or die, know only the truth with set you free from your guilt."
The bodies of four people were discovered inside the third-floor apartment suite above a store after firefighters extinguished the vicious blaze that was started in the early morning hours of Feb. 5, 1990.
Helga Rochon, 45, and her daughters Sherri, 26, and Pauline, 19, were killed, along with Pauline's seven-month-old daughter Kimberly.
Another sister and the couple who lived in the suite below the family managed to escape.
The matriarch had been president of the Prince Rupert Lioness Club and was known for raising money for a charity telethon, her daughter Lorraine Rochon recalled. Her sister Sherri had a photographic memory, graduated the top of her class and was growing her career as a marine biologist. Pauline was a smart and career-oriented, driven young woman and mom, added her sister.
Narrowing the search for the arsonist is a renewed goal of Mounties in B.C., added Supt. Ward Lymburner at the provincial RCMP headquarters.
"We are certain that someone has information to allow our investigators to solve this crime," Lymburner said. "But they have not brought that information forward previously. They now have an opportunity to find answers for Helga, Sherri, Pauline and Kimberly."
Police know the fatal fire was a second attempt of arson at the building in three months, he said, but he declined to give more details about the fire or about the letter.
Investigators have not limited their scope to where the information provided by the letter may have originated, he added, noting one or more suspects could have moved throughout B.C. or Canada over a quarter century.
Police are aware of the content of the letter and are attempting to contact its author, he said.
Rochon said it was received by the husband of one of her sisters, "giving us more questions than answers, with no way of knowing who sent it or where it came from."
Police have labelled the crime a homicide, but Lymburner could not say whether the arsonist was intending to target to kill.
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— By Tamsyn Burgmann in Vancouver
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