Burglars have entered several homes in Half Moon Bay through unlocked garage doors or side doors, and the San Mateo County Sheriff’s Office is warning residents to be alert. Burglaries have occurred on the 1000 block of Third Avenue, on the 400 block of Grand Boulevard and on the 300 block of Valdez Avenue, according to Sgt. Jim Gilletti. The burglaries have mostly occurred during daylight hours. Gilletti noted that in other jurisdictions, thieves have often walked door to door, knocked on doors and then enter through a side or garage door once they have determined no one is home. If someone answers the door, they will make up a phony reason for knocking. Residents who see something suspicious should call sheriff’s dispatch at (650) 363-4911.