Fires killed 57 people in Minnesota last year, the largest number in 14 years, according to figures released Monday by the Department of Public Safety's State Fire Marshall's office.

It represented a 30 percent increase over the 44 people who died in fires in each of the previous two years, and was the most since 2002, when 64 people perished.

Careless smoking was the leading cause of fatal fires, accounting for nine deaths. Unattended cooking was responsible for four deaths, while suicide was blamed in three deaths and arson in two. There were 24 fire deaths in which the cause could not be determined, State Fire Marshal Bruce West said.

"This increase is heartbreaking because most of these deaths were preventable," West said.

March and October had the most deaths in 2015, each with seven. The fewest occurred in June and November, each with two.

To date, there have 14 deaths statewide this year. That compares with 27 at this time last year, spokeswoman Jen Longaecker said.

West offered several tips for remaining safe, including leaving 3 feet between a candle from anything that could burn or using the flameless variety, keeping space heaters 3 feet from anything combustible and never leaving a hot stovetop or oven unattended.

Smoking should be done outside, and cigarettes should not be discarded in potted plants, leaves or mulch. Cigarette butts should be completely extinguished and disposed of in a metal container filled with water or sand, West said.

Minnesota recorded a record-high 134 fire deaths in 1976.

Tim Harlow