San Mateo police are looking for a man who posed as a county sheriff’s deputy. Surveillance video shows the man walking into the Safeway in the Crystal Springs Shopping Center about 9 p.m. on Tuesday, Nov. 24. Employees say the man, dressed in a deputy’s uniform, claimed he was investigating a theft and demanded to speak to someone inside the store’s office, where the money is kept. An employee told the man that no theft had occurred and refused to let him inside the office. The suspect left the store a short time later.After reviewing the surveillance footage, the San Mateo County Sheriff’s Office says the man is not a deputy with the department. Police continue to search for the suspect. Anyone who recognizes him is asked to contact San Mateo police.