Police are investigating a break-in at a subway in North Hollywood. The suspects forced their way in, smashing out a window at the Subway along the 6000 block of Lankershim Boulevard around 4:00 Saturday morning. The restaurant was closed at the time. It’s unclear if any cash or items were taken. For years there has been an ongoing problem of burglaries involving Subway in the San Fernando Valley, forcing the chain to close its restaurants earlier, according to police. No suspect description has been given.