Police in Canada say they've foiled a Valentine's Day plot to carry out a mass shooting at a mall in Halifax, Nova Scotia.

Dan Karpenchuk, reporting from Toronto for NPR, reports that one person was found dead and three others taken into custody on Friday by the Royal Canadian Mounted Police in connection with the alleged plot, which authorities say was not related to Islamic terrorism. The suspects reportedly planned to kill as many people as possible before committing suicide.

The Associated Press quotes an unnamed police official as saying the RCMP acted on a tip that came in on a Crime Stoppers hotline.

A 19-year-old male suspect killed himself after police surrounded his home early Friday morning. The AP says: "a 23-year-old woman from Geneva, Illinois, was arrested at Halifax airport and confessed to the plot, the official said, adding that she had prepared a number of pronouncements to be tweeted after her death."

Police said two others, males aged 20 and 17 from Nova Scotia, were also arrested in connection with the plot, but their exact role was still being investigated. The 17-year-old was wanted for threatening to shoot up a high school and had an outstanding warrant.

The AP, quoting the unnamed officials, says "the suspects used a chat stream and were apparently obsessed with death and had many photos of mass killings."

The Halifax Chronicle Herald quotes Canada's Justice Minister Peter MacKay as praising law enforcement in acting quickly to avert a tragedy.

"Based on what we know so far, it would have been devastating," MacKay said. A day known to represent love and affection could have taken a much different meaning today had it not been for the exceptional efforts of the combined law enforcement community."

"While this particular incident doesn't appear to be motivated by terrorism, we believe, in particular, some of the online investigations that are required to avert this type of activity do require changes in the legislation and that's why current legislation is before Parliament," MacKay said.

"This appeared to be a group of murderous misfits that were coming here or were living here and prepared to wreak havoc and mayhem in our community," he said.

A duplex where a 19-year-old man was found dead is shown in Timberlea, Nova Scotia, on Friday. Royal Canadian Mounted Police say they foiled a plot to commit a mass shooting.