A police department spokesperson said one of the 57 people injured appeared to be in critical condition.
"People were thrown into the air and onto the ground," passenger Elizabeth Banta told CNN. "There were definitely many people on the ground who were not moving."
More top news
Newly released emails to a Muslim campaign group reveal Mohammed Emwazi felt "controlled" under the watch of the security services.
Five members of the Armed Forces have been granted operational honours and awards in recognition of their service.
The Conservative peer said he was 'shocked' that the law had been vetoed by the Liberal Democrats.