SAN FRANCISCO (CBS SF) – Four people were hospitalized, including two police officers, when two San Francisco Municipal Railway light-rail vehicles where involved in crashes on the Third Street rail line Friday morning.

The first accident occurred when a train struck the side of a police car in the city’s Dogpatch neighborhood shortly before 5:45 a.m. at the intersection of Third and 22nd streets.

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In that incident, Muni vehicle was traveling north on Third Street when it struck the driver’s side of a marked police car, police spokesman Sgt. Daryl Fong said.

KCBS’ Tim Ryan Reports:

The Muni vehicle was not going at a high speed, fire department spokeswoman Mindy Talmadge said.

Two officers in the police car suffered minor injuries in the crash, as did the male Muni operator and a female passenger on the LRV, Fong said.

The two officers were taken to San Francisco General Hospital while the two people on the Muni vehicle were taken to California Pacific Medical Center’s St. Luke’s campus. All four victims’ injuries are not considered life-threatening, he said.

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A second crash happened around 9:13 a.m. at 3rd and King Streets near AT&T Park. A train collided with a Honda sedan and blocked the intersection for the better part of an hour.

The second wreck involved an outbound K-Ingleside train, spokesman Paul Rose said.

Rose said that people traveling in the car refused medical treatment at the scene and that there were no reported injuries in the Muni vehicle.

Muni and police officials are continuing to investigate the cause of each crash.

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