Three passengers aboard a bus that crashed into an overturned semitrailer in Nebraska on Thursday say the driver may have been on the phone at the time of the collision that injured dozens — a claim investigators dispute.

Five people were hospitalized in Kearney, about 180 miles west of Omaha, after the crash around 2 a.m. Thursday involving two semitrailer trucks and a Denver-bound bus. But most of the 41 people who were taken to the hospital had only minor injuries.

The Nebraska State Patrol said after the first semitrailer overturned in the westbound lanes of Interstate 80 near Gibbon, a second semitrailer clipped it. Then the bus struck the overturned semitrailer .

"All of a sudden, you hear the driver say, 'Oh, my God.' Boom. It just disintegrated. Something you wouldn't expect to see in a lifetime," Jimmy Strickland said.

During the collision, Strickland said his six-month-old son slid underneath a seat in the back of the bus. Strickland said it was chaotic after that.

Strickland and fellow passengers, Anthony Pavarotti and Heather Howell, say the driver may have been on her cell phone. But Nebraska State Patrol spokeswoman Deb Collins said the initial investigation showed the cell phone was not in use when the accident happened.

Howell, who was traveling from Davenport, Iowa, to Eugene, Ore., with her husband Joshua Marquez, said she saw the driver talking on the phone on the leg of the trip from Omaha to the crash site.

"She was swerving. I thought she was falling asleep but she was awake the whole time. She was on the phone the whole time from Omaha," Howell said. "Another 18-wheeler missed the trailer laying in the middle of the road. She wasn't paying attention."

American Bus Association spokesman Dan Ronan said the bus company prohibits personal cell phone calls, but the company's drivers use cell phones to communicate with dispatchers, other bus drivers and terminals along the route.

"There's no indication she was doing anything improper," Ronan said.

Collins said the first semitrailer overturned after the driver drifted into the median and overcorrected.

Collins said it wasn't immediately clear how long the first truck had been blocking the interstate before the second truck and bus hit it. The accident closed I-80 for about 4 ½ hours. It reopened around 6:30 a.m.

Officials said the Burlington Trailways bus driver — 50-year-old Michelle Anderson, of Omaha — was in critical condition at the hospital Thursday afternoon. The driver of the first semi — 39-year-old Mohammed Arguini, of Antioch, Tenn. — was in fair condition.

One of the bus passengers — 77-year-old Barbara Bishop, of Hemet, Calif. — was in serious condition Thursday. Two other passengers were in fair condition; they are: 48-year-old Danny Briggs, of St. George, Utah; and 50-year-old Willie Abner, of Birmingham, Ala.

The 61-year-old driver of the second truck was not hurt.

Good Samaritan Hospital spokeswoman Marsha Wilkerson said 30 people were treated and released, and some refused treatment.

Pavarotti, 53, told the Kearney Hub that he was awake and sitting four rows behind the driver when the crash happened.

Pavarotti said the bus was in the left-hand lane being passed by the second semi on the right when it came upon the overturned semi, so he said the bus went right through the trailer full of dried cereal.

Pavarotti, who is homeless, said his 4-year-old service dog was killed in the crash.

"I'm having a hard time dealing with it. We've never been separated. Never been separated," he said to the Kearney Hub.

Thomas Laulunen, of Duluth, Minn., said he had his eyes closed when the bus plowed into the truck's trailer, and he went flying upon impact.

Passengers described jumping through windows with some assistance from people at the scene. Laulunen said he caught a glimpse of what appeared to be a wooden wall at the front of the bus that he later determined was from the trailer the bus crashed into.

"This bus cut the trailer right in half," Laulunen said, adding it took about 45 minutes for rescuers to cut the driver out of the wreckage.

Hope Gray, who was returning to San Diego from New York, said the crash woke her up in her seat near the driver.

"And then there was blood right in front of me. It was a horrible sight," said Gray, who wasn't injured.

The passengers who were treated and released from the hospital spent about two hours at an American Red Cross shelter until the bus operator, Burlington Trailways, could get another bus there. They resumed their trip around 8:30 a.m.

Those remaining passengers reached Denver around 3 p.m. Mountain Thursday. The bus company offered them pizza when they arrived and had insurance adjusters ready to talk with passengers.

Ronan said federal transportation records show Burlington Trailways, based in West Burlington, Iowa, has a clean safety record with no accidents in the past two years. Data for previous years wasn't immediately available.

Ronan said Anderson has had her commercial license for nearly 10 years, including seven years driving for Burlington Trailways. He said she had logged 824,000 miles without an accident or moving violation.

The bus was new, having been put into service just two weeks ago, and was fully equipped with seatbelts. Ronan said seatbelts are becoming more common on newer commercial buses, but passengers are not required to buckle up.

The State Patrol was investigating the accident.