Two are dead and 21 injured after a tour bus shortly after 3 p.m. Wednesday landed on its right side after crossing a grassy median and somehow avoiding oncoming traffic on Interstate 90 three miles west of Austin, according to the Minnesota State Patrol.

The bus belonged to Strain Motorcoach Tours of Rochester. It was headed back to Rochester following a day trip to Diamond Jo Casino in Northwood, Iowa, according to a Strain representative.

Though the State Patrol said it could be weeks before a cause is determined, the Rochester Post-Bulletin this morning reports the “52-year-old driver suffered a ruptured aneurysm in his chest” after speaking with the bus company. The driver is Ed Erickson of Elgin.

Renee Benesh, event sales manager at Diamond Jo Casino, said people from Strain Motorcoach Tours have been coming to the casino since around the time Diamond Jo opened in 2006 and said the passengers Wednesday were mostly over 65.

Capt. Matt Langer of the State Patrol said the bus was eastbound when it crossed the median and crossed the westbound lanes before coming to a rest on its right side in the north ditch. The call for assistance came at 3:09 p.m.

He said 14 passengers initially were transported to Austin Medical Center, six to Naeve Hospital in Albert Lea and the bus driver was airlifted to St. Marys Hospital in Rochester. He said the medical conditions of the passengers range from minor to critical.

Langer said the road conditions were normal at the time of the rollover and said no other vehicles were involved. The bus is a 1989 MCI. He said the State Patrol is speaking to witnesses and considers the passengers to be witnesses, too.

He said the State Patrol is the lead agency in the investigation and is being assisted by the Freeborn County Sheriff’s Office. The National Transportation Safety Board has been notified.

“This is a truly tragic event,” Langer said. “Everyone was returning from what was likely an enjoyable outing. Our thoughts and prayers are with the victims and their families.”

Passenger Ardell Swanson, 71, of Austin, said she was just putting her head back to rest when the bus crashed.

“When I got myself organized there was all kinds of red and white and blue lights flashing,” Swanson said. “There was glass all over.”

Tammy Eggum of Hayward was driving westbound when she saw the bus cross the median. She said the bus became airborne.

“It was like the movie ‘Speed,’” she said. “I was just concerned about stopping, hitting my brakes and couldn’t believe what I saw.”

Eggum said she saw the bus “slam” into the ditch. She and others pulled over and got out first aid kits and blankets. She called 911, which connected her to the Minnesota State Patrol.

She said the driver was hurt and still conscious. The bus was on its right side, the side with the door. The good Samaritans attempted to open the two hatches atop the bus but they wouldn’t open. They only open from within.

Rich and Paula Schultz were driving from Austin to their home in Wells with Paula’s mother, Dorothy Garver. They saw the bus in the ditch and stopped to help.

Rich Schultz said a passenger opened the hatch closer to the front of the bus. A man crawled in the hatch and made his way to the rear to open that hatch. He said though the front window was busted open, it looked difficult to go out that way.

He said they soothed the passengers’ worries while they waited for authorities to arrive. Soon, a Mower County deputy showed up with a first aid kit. (Though the crash was in Freeborn County, it was only three miles from the Mower County seat.)

Then a state trooper arrived and extrications began.

Eggum said she helped a woman who she said was not seriously injured. She made it out of the bus, then sat with her and one other woman, offering comfort. Eventually, a group of elderly people with bruises and cuts were sitting on the side of the ditch. Some with blankets and some needing blankets. It was 48 degrees and overcast at 3:30 p.m.

At first, the westbound lanes were limited to one lane. Soon, the entire freeway, east and west, was shut down. Motorists were left to sit in place. Some, including an Albert Lea school bus driver, went through the grassy median to find another route. Spectators parked cars on a gravel road that fronts I-90 to the south.

Meanwhile, ambulances from many places crowded the location. In addition to state troopers and sheriff’s deputies from Mower and Freeborn counties, first responders included Albert Lea Medical Center, Austin Medical Center, Austin Fire & Rescue, Adams Ambulance, Ellendale Ambulance, Freeborn Ambulance, Gold Cross Ambulance, Hayward Fire, Albert Lea Township Fire, Glenville Fire, Myrtle Fire, London First Responders. There probably were others, too.

Two helicopters landed on the closed eastbound lanes of I-90. One was Mayo One, while the other was LifeNet, an air medical service with operations in Iowa, among other states. The driver was taken via Mayo One. The other chopper left empty.

Once everyone was out of the bus and transported, large wreckers were positioned to lift the bus. Once ready to lift, a state trooper asked the media to move away from the bus because of the unpleasantness of sight.

Langer said the bus had no seat belts, and when it overturned, some passengers were trapped underneath.

Motorists who had been stranded were allowed to continue through at 5 p.m. Otherwise, Interstate 90 between Exit 175 in Austin and Exit 166 at Petran was shut down as authorities conducted their investigation into the night. The rollover happened at milepost 172.

The driver was in serious condition Wednesday night at St. Marys Hospital in Rochester, where two passengers also were in critical condition. Langer said the driver had been interviewed.

Mayo Dr. Chris Farmer said two of the injured taken to Austin Medical Center were later transported to St. Marys Hospital in Rochester.

Of the 11 remaining at AMC, eight were hospitalized, which means 14 of those injured in the crash were hospitalized in all, including the three sent to St. Marys and three more in Albert Lea.

“Today, we had a tragedy,” Farmer said. “Our condolences go out to the families of those who died.”

The names of those in the hospital are not being released by Mayo because not all of the families have been notified.

The Strain representative said the casino trip takes place every Wednesday, picks up passengers at Rochester and surrounding areas in the morning, arrives at the casino around 11 a.m., then heads back after roughly four hours at the casino.

The representative said the bus left the casino Wednesday at about 2:30 p.m. and was scheduled back into Rochester at about 5 p.m.

The representative confirmed that out of the 23 passengers, seven were picked up Wednesday at the Cub Foods in Rochester, six were picked up in Kasson, eight were picked up in Byron, one was picked up in Blooming Prairie and one boarded at the Strain Tour Office in Rochester.

According to Federal Motor Carrier Safety Administration records, Bold Lines Inc., which does business as Strain Tours, has not had any crashes in the past 24 months and received a “satisfactory” safety rating in May of this year.

Strain Tours operates with four buses and six drivers, according to records.

In 2002, Bold Lines paid $20,000 to settle an enforcement case over drug testing for drivers, according to the federal safety agency. It also paid $300 to settle a case over driver duty times and recordkeeping.

The agency has advised roadside inspectors to inspect the company’s vehicles because of safety concerns, according to the Web site. Its “Inspection Selection System” rated Strain at a 76, with any score between 75 and 100 meaning an inspection is warranted.

Benesh, of Diamond Jo Casino, added that the bus drivers with Strain Motor Coach Tours are great people to work with.

“They’re the most wonderful group of people ever,” she said. “It’s very, very sad.”

Mayo officials said there were two other collisions in Rochester after the bus rollover Wednesday evening. One involved a school bus and a car. Eight children were in the bus and had minor injuries; one in the car had moderate injuries and one was in serious condition. Those two were taken to St. Marys. In addition, an ambulance on the way to that accident collided with a car. Two were injured and taken to the hospital.

Mayo Dr. Beth Ballinger said the injuries from all three wrecks were typical of crashes, including head injuries, spine injuries, scrapes etc.

“We drill and train for something like this,” Ballinger said of the heavy load at the hospital.

— Sarah Stultz, David Richards and The Associated Press contributed to this report.