OAKLAND (KPIX 5) – Police in Oakland are searching for vandals who defaced a freeway sign paying tribute to four officers who were killed on the deadliest day in department history.

According to authorities, the sign was knocked down and defaced with a red “x” sometime on Friday.

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The sign honors Sgt. Mark Dunakin, Sgt. Ervin Romans, Sgt. Daniel Sakai and Officer John Hege. On March 21, 2009, all four officers were killed by a convicted felon on parole. The roadside sign was installed three years after their murders and has become a fixture along Interstate 580.

Friday’s vandalism comes after weeks of anti-police brutality protests across the Bay Area, with officers frequently facing off in skirmish lines with protesters.

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In a written statement, the Oakland Police Department said, “This act of disrespect does not represent the majority of our community’s feeling about the Oakland Police Department. We have received overwhelming support in recent weeks regarding our hard work, dedication and professionalism during these difficult times. The sign will be repaired and the officers’ sacrifices will never be forgotten.”

Officers are investigating the vandalism. Police don’t have any suspects.

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