PATERSON, NJ - City police are investigating whether four armed robberies at Northside grocery stores since New Year's Eve are connected.

The most recent robbery happened Sunday night at about 9:40 pm at the grocery store at 22 Paterson Avenue, police said.

Four gunmen dressed in black wearing ski masks robbed the owner of the money in the register and four customers of all the money they had, said Lt. Richard Reyes. "This matches the MO (modus operandi) of the others we had,'' said Reyes.

Margarita's grocery on Haledon Avenue has been knocked off twice since New Year's Eve. A third grocery also has been hit bu armed robbers, Reyes said.