Comedian Tracy Morgan was reported recovering Sunday following a deadly chain-reaction crash on the New Jersey Turnpike as federal investigators began examining the accident.

Morgan, 45, is expected to remain hospitalized for several weeks. The former "Saturday Night Live" and "30 Rock" alum underwent surgery for a broken leg at Robert Wood Johnson Hospital in New Brunswick, New Jersey, and remained in critical condition, the Associated Press quoted Morgan spokesman Lewis Kay as saying.

In addition to a broken leg, Kay said Morgan suffered a broken and several broken ribs.

The accident killed comedian James "Jimmy Mack" McNair and critically injured Morgan assistant Jeffrey Millea, 36, of Shelton, Connecticut, and comedian Ardie Fuqua Jr. 43, of Jersey City, New Jersey.

Tyrone Gale was driving Morgan's limo bus. He told ABC he "heard Tracy screaming for help" but he was unable to reach him.

Kay told ABC Morgan was "more responsive" Sunday, calling it "encouraging."

The driver of the tractor-trailer that plowed into Morgan's limo bus, Kevin Roper, 35, was released on $50,000 bond.

New Jersey State Police said it appeared Roper was dozing when the accident occurred.

Meanwhile, the National Transportation Safety Board sent a team to investigate the accident, the Times of Trenton reported. Investigators arrived early Sunday to begin collecting evidence.