The train departed at 04.20 on Saturday morning from Stockholm Central Station. About 14 minutes later, it got out of hand.
Now documents obtained by SVT show that there were several known faults on the rails where the train derailed. In the inspection report, it appears that just over two weeks before the derailment, an investigator found that there were cracks in the switchboard where the derailment began.
"Cracks found in switchboard 106 during maintenance," wrote a railway worker on May 9.When the train to Arlanda passed the same place on the morning of May 27, it derailed and two people were injured.
The Accident Investigation Commission quickly arrived at the scene to investigate the cause and now the police have also decided to initiate a preliminary investigation into causing danger to others and causing bodily harm.
"There were both passengers and staff on the train at the time of the derailment. There has been a risk for everyone on the train to be seriously injured, says Robert Björk, detective inspector and head of investigation at the police.
At this time, there is no suspect.
The company A-train, which manages the operation and maintenance at the site where the train derailed, admits that there have been problems.
Have there been inspection remarks at this particular location?
– Answer yes. We have concerns about the facility," says Magnus Zetterberg, CEO of A-train, which operates Arlanda Express.
Were there remarks in this particular location that were not addressed?
"I have no indication that there was any remark that was not addressed. Now we are refueling all systems to provide information to the Accident Commission, says Magnus Zetterberg.
SVT has previously examined how trains have derailed due to known errors and shortcomings, then it has usually been about freight trains on the Swedish Transport Administration's railway network. In none of these cases has anyone been convicted of a crime.
Were you on the train? Or do you know more about the reason? Email SVT's investigative reporters here.