FARMINGTON, Mich. -

Farmington police say there will be extra patrols and backpack checks at Farmington High School Monday after a “suspicious” phone call was received.

Police said the call came in around 1 a.m.

The caller was “speaking in a very low voice and made a threat against students for April 21 and hung up,” police said in a statement.

Police said the school was swept by a Michigan State Police bomb-sniffing dog, and nothing was found to make the threat credible. However, police will continue to work with district administrators on the investigation.

Anyone with information is asked to contact the Farmington Public Safety Department at 248-474-4700.