Westfield police are asking for help locating Susan Griffin, 48, who was reported missing by her family Tuesday evening.

"She was last seen in the Greenfield, Mass. area," the Westfield Police Detective Bureau wrote in a Facebook post. "Due to recent changes in her behavior, family members are concerned for her well being."

Griffin's sister, a West Springfield resident, called police shortly after 5 p.m. Tuesday, telling them that Griffin had left her letters that expressed emotional distress, according to a Westfield police report. Griffin had left her sister her house keys and told her to take care of her cats, according to the report.

West Springfield police asked Westfield officers to check on Griffin, but they did not find her at her Meadow Street apartment.

Police describe Griffin as five feet four inches tall and 120 pounds with brown eyes and dark hair with a patch of gray on top. Anyone with information in the case is asked to call the Westfield Police Department at (413) 562 5411