Authorities say the man tried to snatch a woman's purse at a Wal-Mart, then drove to the nearby Shaw's lot and locked himself in his vehicle, threating to harm himself and others.

AUBURN, Maine (AP) _ Officials have evacuated the Auburn Mall and a Shaw's supermarket as police negotiate with an armed man who's sitting in a Jeep in the Shaw's parking lot.

Police Chief Phil Crowell says an Auburn man tried to snatch a woman's purse in a Wal-Mart parking lot around 11 a.m. Monday and fled when police responded.

Crowell said the man drove to the nearby Shaw's lot and locked himself in his vehicle, threating to harm himself and others. Police are treating the situation as an armed standoff.

A Maine State Police tactical team and negotiators are assisting Auburn police.

The Sun Journal reported that police have blocked off a section of heavily traveled Center Street as well as the Veterans Memorial Bridge that connects Auburn and Lewiston.