It happened just after 7:15 p.m. at East 23rd Street and First Avenue in Kips Bay.
There was a tangled mess of metal and glass after an X38 MTA bus and a TopView Sightseeing double-decker bus crashed.
"The impact felt like it was almost an earthquake. The whole bus was rattling and shaking," said Ishrak Jahan, who was on the eastbound city bus. "I heard the lady next to me scream, so I looked up and I saw this bus barreling towards us ... I just saw glass everywhere for a second. I, you know, it was honestly like I was in a movie. It took a couple of seconds for me to snap back to reality when everyone started screaming. I saw blood."
Pillan and his family were on the tour bus as it headed up First Avenue.
"A lot of people thrown out of their seats. Injured, a lot of injuries. A lot of old people injured," he said.
Some passengers, like Paulina Rychel, were hit by a wave of glass.
"I heard it before I felt it. I heard the boom and then I felt it," she said.
Firefighters had a challenge taking people off the second deck of the tour bus and going through windows to take people out.
Fire officials say 27 people have been taken to local hospitals, including the tour bus driver, and about 50 others are being checked out.
MTA investigators say the tour bus was at fault in the accident.
"This tour bus ... seemed to have blown a red light and T-boned our bus. Hit it actually twice, it was going so fast, we think," New York City Transit President Richard Davey said.
According to officials, no one suffered life-threatening injuries, and most of the injuries involved cuts, bruises, some suspected fractures, and some head and neck injuries.
"We're all quite fortunate it was not much worse," Hopper said.
Passengers were relieved the injuries were not more serious.
Rachel thought she was taking the safe way home.
"It's crazy because I'm always like, oh, the bus is so safe and I never take the subway because the bus is better. Yeah, it's crazy," she said.
Police sources tell CBS New York the tour bus driver will be summonsed for allegedly running the red light.
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