Morgan, 45, who suffered a broken leg, femur and nose and several broken ribs in the June 7 crash, has been transferred to an undisclosed rehab center where he is expected to remain for the next few weeks, said Morgan's publicist, Lewis Kay.
The former Saturday Night Live and 30 Rock star, along with his fiancée, Megan, expressed their "deepest gratitude" to everyone at Robert Wood Johnson University Hospital in New Brunswick, N.J. for the "unbelievable care and attention they provided him," Kay said.
"While he is continuing to show signs of improvement, he still has a long way to go," Kay said.
The Cranbury, N.J. crash killed a Peekskill, N.Y. man, while two others - a 36-year-old man from Shelton, Ct. and a 43-year-old man from Jersey City - were last reported to be in critical condition at Robert Wood Johnson University Medical Center, said Zenaida Mendez, spokeswoman for the hospital.
Morgan's limo bus overturned in a collision on the New Jersey Turnpike in Cranbury, N.J. that killed James McNair, 63, a passenger. The remaining passenger was treated at the hospital and was released.
Kevin Roper, 35, of Jonesboro, Ga., 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 van at 1 a.m., according to the Middlesex County Prosecutor's Office. He has pleaded not guilty to the charge.
Roper surrendered at the New Jersey State Police Cranbury Station and was lodged in the Middlesex County Jail in North Brunswick Saturday. He was released after posting $50,000 bail.
Walmart released a statement to the media saying the department-store chain is "profoundly sorry that one of our trucks was involved" and that the company will cooperate fully with law enforcement.
“The facts are continuing to unfold. If it’s determined that our truck caused the accident, Walmart will take full responsibility," according to a statement reported on Business Insider.
A preliminary investigation determined that the tractor-trailer crashed into the van, a 2012 Mercedes Sprinter, as both vehicles traveled in the northbound lanes of the New Jersey Turnpike. Four other vehicles were involved in the crash. None of the occupants of those vehicles was injured, according to the prosecutor's office.
The cause of the crash remains under investigation.
Anyone with information is asked to call the New Jersey State Police Detective Bureau at the Troop D Station in Cranbury at 609-860-9000, extension 4400.
Various reports from ABC News and elsewhere provided new details on the crash, noting that Morgan allegedly screamed for help after his limo bus overturned.