PLYMOUTH, Mass. (AP) — Authorities say smoking may have caused an overnight fire that killed a man in Plymouth.

The Plymouth district attorney's office said Wednesday that state and local fire investigators haven't found anything suspicious about the fire.

Firefighters who arrived just before 2 a.m. found the multi-unit apartment building engulfed in flames. Officials said the fire began in a second-floor bedroom where the man was found. They said the cause appears to be improper disposal of smoking materials.

The victim's name has not been made public.

There have now been 17 fire-related deaths in Massachusetts this year.