Norwegian police on Tuesday said a failed asylum seeker from South Sudan was suspected of killing three people on an express bus the day before, but his alleged motive remained unknown.

As of midday on Tuesday, police had not been able to interview the suspect, who was reported aged around 30 and being treated for minor cuts at Haukeland University Hospital in the west coast city of Bergen.

Ronny Iden, police chief in the Sogn and Fjordarne police district, and police prosecutor Jorn Lasse Refsnes told reporters the motive for the attack remained unknown. They did not know whether the suspect had been aware that he was due to be deported from Norway on Tuesday.

The victims were a 19-year-old woman and two men in their 50s. One of the men was the Norwegian driver of the bus; the other was a Swedish passenger. The three apparently died from stab wounds, but were to undergo autopsies.

Forensic tests were also due on a knife found on the coach, which was bound for Oslo, the capital.

Tor Brekke, deputy head of the asylum centre in the small town of Ardal where the suspect had lived since August, said the man’s asylum request had recently been rejected.

Mr. Brekke told public broadcaster NRK the man had been due to be sent back to Spain, where he had initially applied for asylum. This was in accordance with the terms in the Dublin Regulation that generally stipulates that refugees must apply for asylum in the E.U. country where they first arrive in the bloc. Non-E.U. member Norway is part of the process.

While at the asylum centre, the suspect had taken part in obligatory activities and did not appear disturbed, Mr. Brekke said.

Investigators from the National Criminal Investigation Service were taking part in the investigation.

Ten years ago, a driver on the same coach service, Valdresekspressen, was stabbed to death by an asylum seeker from Ethiopia. The 26-year-old was later ordered into psychiatric care.

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