(CNN) — Actor Tracy Morgan and two others remained in critical condition Sunday after a chain-reaction wreck that killed a fellow comedian.
The three patients were being treated at Robert Wood Johnson University Hospital in New Jersey on Sunday, hospital spokeswoman Zenaida Mendez said.
The crash early Saturday morning killed James McNair, 63, who was riding in a limo bus with Morgan.
McNair was a comedian who performed under the name Jimmy Mack, said his sister, Valerie Daniel.
“He spoke very highly of Tracy,” she said. “They go way back.”
Walmart employee charged
Truck driver Kevin Roper, 35, was charged with one count of death by auto and four counts of assault by auto after the tractor-trailer he was driving crashed into the limo bus, a statement from Middlesex County Prosecutor’s Office said.
Walmart spokeswoman Brooke Buchanan said the truck driver is an employee.
“This is a tragedy and we are profoundly sorry that one of our trucks was involved,” Bill Simon, president and CEO of Walmart U.S., said in a statement.
“The facts are continuing to unfold. If it’s determined that our truck caused the accident, Walmart will take full responsibility.”
The wreck occurred about 1 a.m. ET on Saturday on the turnpike in Mercer County, Sgt. Gregory Williams of New Jersey State Police said.
“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.”
Four other vehicles were involved in the crash, the prosecutor’s office said, but no one in those vehicles was injured.
Williams said he does not believe alcohol played a role in the crash, 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.
From SNL to “30 Rock”
Morgan, 45, was a regular on “Saturday Night Live” for seven years. He later received an Emmy nomination for his role in “30 Rock,” in which he played Tracy Jordan, an exaggerated version of himself.
The New York City native made his reputation with over-the-top characters and impressions of celebrities such as Mike Tyson and Oprah Winfrey.
Morgan performed a comedy tour act Friday night at the Dover Downs Hotel & Casino in Dover, Delaware, the venue said.
Christopher Thompson, spokesman for limo owner Atlantic Transportation Services, said he thought the limo bus was heading to drop Morgan off in New Jersey.
The actor received messages of support and concern on Twitter.
“Wishing a speedy recovery to our friend @RealTracyMorgan,” tweeted SNL Weekend Update.
“Shocked to wake up and read that @RealTracyMorgan is injured. Love to Tracy and wishing him strength,” said former SNL cast member Rachel Dratch.
“My thoughts are with Tracy Morgan and his family. I hope he pulls through this soon and gets back to making us laugh!” said Joan Rivers.
“Saying a prayer for @RealTracyMorgan,” said actor-director Jon Favreau.
“Come on @RealTracyMorgan pull through this buddy,” tweeted actor Ike Barinholtz of “The Mindy Project.”
CNN’s Suzanne Presto, Faith Karimi, Rachel Wells, Carma Hassan, Joe Sutton and Alexandra Field contributed to this report.