(UPDATE 10:24p) Police are clearing the location - No crime.
Re: Police activity in the area of 3300 Blk Countryside 
(Update 10:24p) After police responded to an incident reported at a location on Countryside, it was determined there was no crime and police are clearing the scene.
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There is a heavy police presence on the 3300 block of Countryside as police investigate a possible disturbance. At this time, the presence is isolated to one location and is precautionary while they determine if a crime has occurred and address the call for service.
Address/Location
San Mateo, CA Police Department
200 Franklin Pkwy
San Mateo, CA 94403
Contact
Emergency: 9-1-1
Non-emergencies: 650-522-7700
TEXT-A-TIP - Text TIP SANMATEOPD followed by your message, to 888777