Comedian and actor Tracy Morgan remains in a critical condition but is responding to treatment. He was involved in a multi-vehicle crash Saturday that killed one.

Morgan underwent surgery Sunday for his broken leg and doctors said he might remain in the hospital in New Jersey for coming weeks. He also suffered a broken nose and ribs, spokesman Lewis Kay said, reports CBS News.

"His family is now with him and he is receiving excellent care," spokesman Lewis Kay said in a statement. "We don't anticipate much of a change in his condition today but will provide a further update once more information becomes available."

The 45-year-old 'Saturday Night Live' star was in  his limousine bus when it overturned on the New Jersey Turnpike. The 6-vehicle pile-up happened around 1 a.m. Saturday in the northbound lanes between exits 7a and 8. James McNair, a comedian and fellow passenger in the limo bus was killed in the accident.

Kevin Roper, the truck driver was charged in the accident after he turned himself in. He was released on a $50,000 bail Saturday night. The 35-year-old native of Jonesboro, Georgia, faces four counts of assault by auto.

"The driver of the tractor-trailer failed to observe slow-moving traffic ahead," Sgt. Gregory Williams of New Jersey State Police said, reports CNN. "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."

Passengers in the four other vehicles involved in the crash were unharmed. It does not seem that alcohol was the reason behind the accident, but investigators have not ruled out the possibility.

The National Transportation Safety Board will look into the "safety issues related to commercial trucking and limousine safety," said board spokesman Keith Holloway. "All I know is I saw traffic ... and I stopped ... and I was upside down and in the vehicle," limo driver Tyrone Gale told WCAU. Gale suffered bruises in the accident.

Walmart President Bill Simon issued a statement saying that one of the firm's trucks was involved in the fatal crash. He said the company will take "full responsibility" if investigators conclude that  Walmart's truck caused the accident.

"We're praying for the family and friends of the passenger who lost his life in the terrible accident" the statement said. "Our hearts go out to everyone involved and we hope those who were injured get the care that they need and make a full recovery."