Tracy Morgan
Actor Tracy Morgan said to be improving following surgery to repair a leg broken in Saturday's crash. Reuters/Mario Anzuoni

Prosecutors Saturday charged the driver of a tractor-trailer with causing the accident that put comedian Tracy Morgan in the hospital in critical condition and left one person dead.

Morgan's limousine bus was hit by a tractor-trailer in a six-vehicle accident on the New Jersey Turnpike, state police said.

Charges were filed against Kevin Roper, 35. He was charged with one count of death by auto and four counts of assault by auto, the New York Times reported.

The former “Saturday Night Live” cast member’s tour bus accidently overturned in Mercer County. The accident involved six vehicles, including two tractor trailers and an SUV, according to CNN.

A preliminary investigation suggested that one of the tractor-trailers caused the crash, reports NBC 10. Of the six passengers in Morgan's tour bus, one person has died while three others are in critical condition, and a fourth with less severe injuries.

According to reports, Morgan, 45, is in intensive care and was taken to Robert Wood Johnson University Hospital Center in New Brunswick, N.J.

Morgan, who starred in NBC's hit "30 Rock," performed Friday night at the Dover Downs Hotel and Casino in Dover, Delaware, CNN reported.

The American comedian gained popularity in 1996 after joining the cast of “Saturday Night Live” and continued performing in the comedy show until 2003. In 2011 Morgan returned to the show as a guest on the Christmas show hosted by Jimmy Fallon.