SAN FRANCISCO (CBS SF) — Four people were hospitalized, one with serious injuries, after the double-decker, open-air tour bus they were on struck a low-hanging telephone line in San Francisco’s Richmond District on Friday, a police spokeswoman said Monday.

The accident was reported at 3:17 p.m. in the 400 block of 12th Avenue near Geary Boulevard and involved a Big Bus Tours San Francisco bus, police spokeswoman Officer Tracy Turner said.

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The bus driver had deviated from the tour’s normal route and was traveling north on 12th Avenue when the bus struck the wire, Turner said.

The wire hit the windshield of the top level of the bus, then struck multiple passengers on the upper deck, according to Turner.

Five people were treated for injuries that included cuts, bruising and scratches. Four ended up being transported to San Francisco General Hospital, including one who was critically wounded, Turner said.

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Andrew Smith, general manager of Big Bus Tours San Francisco, said he was unaware of someone suffering serious injuries in the accident. He said the three other passengers were released from the hospital hours later and took the company’s night tour of the city.

Smith said the bus was on a secondary route that is checked frequently for safety reasons.

He said the company’s “concern is for the safety of the customers” and that that Big Bus Tours cooperated with the police investigation into the accident.

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