The comedian continues to recover from Saturday's accident

Credit: Robin Marchant/Getty

Tracy Morgan had a “better day” in the hospital Thursday as he recovers from a deadly car crash, his rep said in a statement to PEOPLE.

“While Tracy remains in critical, but stable, condition, he continues to show signs of improvement,” the statement read. “His medical team remains optimistic that his recovery is progressing.”

The 30 Rock star was injured after a Walmart truck caused a six-vehicle accident on the New Jersey Turnpike early Saturday. His comic mentor James McNair was killed and two others, including his assistant, Jeffrey Millea, were seriously injured in the crash. Truck driver Kevin Roper pleaded not guilty to vehicular homicide and assault by auto charges during an arraignment Wednesday.

Meanwhile, Morgan, 45, has stayed in the intensive care unit at Robert Wood Johnson University Hospital in New Brunswick, New Jersey, as his fiancée Megan Wollover watches over him. He successfully underwent leg surgery Sunday.

“Megan remains by his side and is relaying the countless good wishes and prayers that his family, friends and fans have been sending their way,” the rep continued. “In addition, Jeff’s wife asked us to pass along that Jeff has also shown much improvement over the past few days. She is very thankful for the love and support she and their family continue to receive.”

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