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San Francisco Tour Bus Crash

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Tour Bus Crash

Emergency personnel tend to the injured after a double-decker tour bus smashed into a bicyclist, several cars and a construction site Friday, Nov. 13, 2015, in San Francisco's tourist-packed Union Square. Authorities say at least 19 were injured, including five critically. (Hoda Emam via AP)

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Tour Bus Crash

An injured man reacts after being involved in a crash near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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Tour Bus Crash

Firemen carry away a passenger injured on an open-air tour bus after it crashed into a construction site near Union Square Friday, Nov. 13, 2015, in San Francisco. Officials say there may have been as many as 30 people aboard the bus. There's no word on the conditions of the injured. (Mike Koozmin/San Francisco Examiner via AP) MANDATORY CREDIT

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Tour Bus Crash

Fire and police assist injured people on an open-air tour bus after it crashed into a construction site near Union Square Friday, Nov. 13, 2015 in San Francisco. Officials say there may have been as many as 30 people aboard the bus. There's no word on the conditions of the injured. (Mike Koozmin/San Francisco Examiner via AP)

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Tour Bus Crash

Emergency personnel tend to the injured after a double-decker tour bus smashed into a bicyclist, several cars and a construction site Friday, Nov. 13, 2015, in San Francisco's tourist-packed Union Square. Authorities say at least 19 were injured, including five critically. (Hoda Emam via AP)

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Tour Bus Crash

Firemen carry away a passenger injured on an open-air tour bus after it crashed into a construction site near Union Square Friday, Nov. 13, 2015, in San Francisco. Officials say there may have been as many as 30 people aboard the bus. There's no word on the conditions of the injured. (Mike Koozmin/San Francisco Examiner via AP) MANDATORY CREDIT

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Tour Bus Crash

Firemen walk an elderly man towards an ambulance near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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Tour Bus Crash

Injured people are tended to by paramedics near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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APTOPIX Tour Bus Crash

People tend to an injured person near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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Tour Bus Crash

Firemen walk a woman towards an ambulance near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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Tour Bus Crash

MUNI workers assess the scene of a crash near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)

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Tour Bus Crash

Firemen wheel an injured man towards an ambulance near Union Square in San Francisco, Calif. on Friday, Nov. 13, 2015. According to The San Francisco Fire Department, a double-decker tour bus crashed into multiple vehicles and pedestrians. (AP Photo/Josh Edelson)