The driver of a Wal-Mart tractor-trailer that slammed into a limo carrying comedian Tracy Morgan last June had been awake more than 28 hours, the National Transportation Safety Board said today. 
 
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 Around 1 a.m. on June 7, 2014, 35-year-old Kevin Roper – then halfway through the 13th hour of his 14-hour shift – slammed into Morgan’s limo from behind, killing comedian James McNair and seriously injuring Morgan and three others. 
 
 Before starting his Wal-Mart shift, Roper had driven 12 hours in his personal vehicle from his home in Georgia to his base in Delaware, according to the NTSB. 
 
 His “decision to drive 800 miles overnight” was “a factor in the crash,” NTSB senior accident investigator Dennis Collins said today. 
 
 Though Wal-Mart provided fatigue information during its driver training, it was not required to have a fatigue management program,the NTSB said. 
 
 Moments before the crash, the trailer was traveling at 65 mph, 20 mph over the construction zone’s 45 mph speed limit. 
 
 “Had the truck driver been traveling at the posted work zone speed limit of 45 mph, it could have been stopped before impact,” NTSB investigator David Rayburn said today. 
 
 Roper's attorney told ABC News he would dispute the NTSB's conclusions. 
 
 The passengers in the rear of the limo’s rear compartment were not wearing seatbelts at the time of the crash, NTSB chairman Christopher Hart announced at a board meeting today, nor had they received a safety briefing outlining the benefits of seat belts. 
 
 After being hit by the Wal-Mart truck, the limo then struck three other vehicles and rolled over before coming to rest on its side on the New Jersey Turnpike. 
 
 Because the limo had been customized, “the passengers had no available exits until emergency responders removed parts of a plywood panel that had been installed,” Hart said today. 
 
 Indeed, it took nearly 40 minutes for first responders to extricate some of the victims from the limo. 
 
 “I shudder to think what would have happened if this vehicle had caught fire,” NTSB board member Robert Sumwalt noted. 
 
 Roper was later charged with one count of vehicular homicide and several counts of assault by auto, with authorities saying they believed he had dozed off behind the wheel. He pleaded not guilty. 
 
 The crash left Morgan, then 45, in critical condition, with multiple broken bones and a traumatic brain injury. 
 
 Since then, the comedian has “struggled” to regain his old self, his lawyer said. 
 
 In a June 2015 interview with “Today” anchor Matt Lauer, Morgan wondered through tears whether he was ever “going to be funny again.” 
 
 He filed a civil suit against Wal-Mart; they reached a confidential settlement in May. 
 
 The retailer, which initially faulted Morgan and his colleagues for not wearing seat belts, later “took full responsibility for the accident,” according to Morgan’s lawyer. ||||| (CNN) -- The truck that rear-ended comedian Tracy Morgan's limo was speeding 20 mph over the limit, and its driver was approaching federal limits on how long he could be behind the wheel, according to investigators. 
 
 The National Transportation Safety Board released a preliminary report Thursday on the New Jersey Turnpike crash that badly injured Morgan and killed one of his friends, comedian James McNair, in the early morning hours of June 7. 
 
 Morgan, 45, suffered broken ribs, a broken nose and a broken leg. His condition has been upgraded from critical to fair, his publicist Lewis Kay said this week. The condition of another limo passenger, Jeff Millea, has also improved to fair, Kay said. 
 
 Hospitalized Tracy Morgan upgraded to fair condition 
 
 A criminal complaint filed by police said driver Kevin Roper had been awake for more than 24 hours at the time of the crash. Roper, 35, pleaded not guilty to charges that include vehicular homicide and assault by auto. He is free on $50,000 bond. 
 
 The NTSB report said the 2011 Peterbilt truck owned and operated by Walmart was speeding at 65 mph for the 60 seconds before the crash. Roper allegedly ignored a sign a mile earlier warning that lanes were closed ahead for construction and another sign a half-mile later reducing the speed limit from 55 mph to 45 mph, the report said. 
 
 The 2012 Mercedes-Benz Sprinter limo carrying Morgan and five other passengers had slowed down because of congestion caused by the center and right lanes being shut down to allow contractors to work on a large overhead sign nearly 3 miles down the road, the NTSB said. 
 
 The truck struck the rear of Morgan's limo, and the "two vehicles moved forward and were involved in secondary impacts with other vehicles that were slowed in the traffic queue," the report said. "The limo van rolled over and came to rest on its left side, facing east, across the center and right lanes." 
 
 Roper, who lives in Georgia but was based in Delaware, reported for work at 11:22 a.m. on June 6, according to the NTSB report. He made deliveries to Walmart stores in New Jersey, Delaware and Pennsylvania before the wreck 13 hours, 32 minutes later, it said. Federal rules limit interstate commercial drivers to 14-hour shifts before they must rest, the report said. 
 
 His total driving time that day was 9 hours, 37 minutes, which is below the 11 hours allowed by federal limits, the report said. 
 
 The NTSB, however, is also looking at how long Roper was awake and driving before he reported to work the day before the crash, officials told CNN on Thursday. He lives in Georgia and commutes to his job more than 700 miles away in Smyrna, Delaware, NTSB spokesman Keith Holloway said. 
 
 Federal investigators based their preliminary findings largely on the small computer on board the truck that records speed, engine performance, brakes and other information, the report said. 
 
 Walmart said last week that it believed Roper was operating within federal rest guidelines but said it would take full responsibility if the investigation shows its truck was to blame. "The details are the subject of the ongoing investigation, and we are cooperating fully with the appropriate law enforcement agencies," said Brooke Buchanan, a spokeswoman for the company. 
 
 The NTSB also released new images of the truck and van based on 3-dimensional scans of them after the crash. 
 
 Morgan was a regular on "Saturday Night Live" for seven years and later received an Emmy nomination for his role in the comedy series "30 Rock." 
 
 Funny man Tracy Morgan has known fame and foibles 
 
 CNN's Mike Ahlers and Rene Marsh contributed to this report.
– How are your reflexes after you've been awake for 28 straight hours? The NTSB says the driver of the truck that smashed into Tracy Morgan's limo was in that exact predicament, reports ABC News. Kevin Roper, 35, drove 800 miles from his home in Georgia to Delaware, where he got into his Walmart truck and embarked on a 14-hour trip, say NTSB investigators. In the 13th hour of that trip, Roper hit Morgan's vehicle on the New Jersey Turnpike, killing one passenger and injuring Morgan and three others. In addition to driver fatigue, the NTSB also notes that Roper was doing 65 in a construction zone, 20mph over the limit, reports AP. “Had the truck driver been traveling at the posted work zone speed limit of 45mph, it could have been stopped before impact,” says NTSB investigator David Rayburn. The agency also says that neither Morgan nor the other passengers in the limo van were wearing seatbelts, which likely made their injuries worse. (Walmart has settled with Morgan, who vows to make people laugh again.)