(CNN) -- Actor and comedian Tracy Morgan was in critical condition after a six-vehicle fatal accident early Saturday on the New Jersey Turnpike, his publicist said.
Morgan's condition was not expected to change Saturday, publicist Lewis Kay said. "His family is now with him and he is receiving excellent care."
The former "Saturday Night Live" cast member and "30 Rock" star was riding in a limo bus when a tractor-trailer struck it in Mercer County, said Sgt. Gregory Williams of New Jersey State Police.
"NJSP says the driver of the tractor-trailer failed to observe slow-moving traffic ahead," Williams said. "At the last minute, he swerved to try and avoid the Mercedes limo bus but struck it from behind, forcing the limo to rotate and overturn."
In addition to the bus, the wreck involved two tractor-trailers and an SUV, he said. One person was killed and seven others were hospitalized with injuries, authorities said.
Police identified the man who was killed as James McNair, 63, of Peekskill, New York. McNair was a passenger in the limo bus.
Peter Haigney, a spokesman for Robert Wood Johnson University Hospital, said four patients were being treated there. Three were in critical condition and one was in fair condition.
Williams said he does not believe alcohol played a role in the accident, but that is under investigation.
The National Transportation Safety Board will investigate "safety issues related to commercial trucking and limousine safety," said agency spokesman Keith Holloway.
Christopher Thompson, spokesman for limo owner Atlantic Transportation Services, said driver Tyrone Gale, who is part owner of the company, was shaken up.
"Although the investigation is still pending, we concur with the preliminary reports that the accident was caused by another vehicle traveling behind the Atlantic limo bus and we are grateful that our drivers did not sustain life-threatening injuries," Thompson said.
Morgan, 45, performed a comedy tour act Friday night at the Dover Downs Hotel & Casino in Dover, Delaware, the venue said.
Thompson said he thought the limo bus was heading to drop Morgan off in New Jersey.
The actor received online messages of support and concern.
"Shocked to wake up and read that @RealTracyMorgan is injured. Love to Tracy and wishing him strength," former SNL cast member Rachel Dratch said via Twitter.
"Come on @RealTracyMorgan pull through this buddy," tweeted actor Ike Barinholtz of "The Mindy Project."
CNN's Rachel Wells, Suzanne Presto, Carma Hassan and Alexandra Field contributed to this report. CNN first learned of the accident from multiple Twitter users.
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