DALLAS (AP) - Dallas police and schools officials are dedicating a historical marker to the police officer shot by Lee Harvey Oswald shortly after the assassination of President John F. Kennedy.

Officer J.D. Tippit was killed 45 minutes after Kennedy on November 22, 1963. Tippit was patrolling the Oak Cliff neighborhood when he spotted Oswald walking down a street. Oswald would shoot him four times.

A passerby used Tippit's police radio to call in the shooting. Oswald was later arrested in the nearby Texas Theatre.

Tippit's widow, Marie, attended a Tuesday ceremony to unveil the marker across the street from the shooting site.

With the 50th anniversary of the Kennedy assassination approaching, Dallas officials preparing for a rush of tourists and interest in perhaps the most notorious day in the city's history.

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