DETROIT (WKZO) -- Detroit police say they received another bomb threat on the Ambassador Bridge Thursday night.

Authorities say the fake threat came in around 5:15 p.m.  However, officials kept the busy international crossing open while they investigated the call instead of closing it.  It's the fourth bomb threat in the past two weeks in Detroit.

A similar threat was made Monday, leading authorities to close the bridge for several hours.  On July 12th, a bomb threat closed the Detroit-Windsor Tunnel, and on Tuesday a threat was made against Comerica Park.