The Clifton Police Department is reminding city residents to remain vigilant and to lock their doors at night following a string of burglaries and home break-ins in nearby Montclair.

“All of the incidents have taken place in the Upper Montclair/Montclair Heights section of the city, however, this does not mean that other areas of the city are immune,” police wrote in a statement.

In these particular incidents, police say thieves are breaking in or attempting to break into homes looking for the key fobs for high-end vehicles.

Police say the thieves are looking for unsecured doors or windows in the homes. They usually dress in dark or black clothing and wear masks. Police also say that the suspects were armed on at least one occasion.

“We are reminding ALL Clifton residents to ensure that your vehicles and homes are appropriately secured every night before going to sleep. Also, do not hesitate to contact us via 911 for any suspicious activity in progress,” police wrote.

Residents are also urged not to confront any of the suspects since they may be armed.