A national bomb protection unit has been flown from Stockholm to northern Sweden after a young man attempted to throw a suspected homemade pipe bomb from a car.

The explosion is the third to rock Sweden in just a few days – after a suspected car bomb detonated in Stockholm on Thursday night and a homemade device blew up in an apartment block in Gothenburg on Friday evening.

A 25-year-old man injured his hand and could have lost an arm, after attempting to throw the devised from a vehicle on the road between Luleå and Boden in the north of the Nordic nation.

“Four places in the Lulea area are blocked off at present. National bombing protection is on the way,” David Levy, a police officer based in the Nord region, told Aftonbladet Sunday night.

The man attempted to reach the hospital on his own after the incident and is thought to have thrown more explosives from the car on the way. He did not make it and was picked up by an ambulance.

Police classed the incident as a disaster endangering the public, and the bomb squad was searching the vehicle and road overnight to make the area safe. The road was re-opened at 4 am.

Polisen misstänker att blodig man slängt ut sprängmedel – stänger av delar av riksväg 97 https://t.co/pj0ifdkRVF pic.twitter.com/ur5EVDPdqz — Aftonbladet (@Aftonbladet) March 12, 2017

“We sealed off the area that was needed because of speculation that he wanted to do away with explosives after he injured himself,” Mr. Levy added, speaking to Expressen.

One witness told public broadcaster SVT the device could be a pipe bomb, but police refused to confirm the report.

“We do not know what it is until the bomb protection unit has gone through what it might be. There is speculation,” said Mr. Levy.

“It seems that he had thrown something out of the car that was explosive, we do not know if it is any kind of home construction or exactly what it may concern,” added Michael Toft, another local officer.

The injured man will face questioning when he is recovering. His car has been seized, and his home searched.

The spotlight has been shone on Sweden and the reported rise in violent crime there since U.S. President Donald J. Trump linked the chaos to unprecedented levels of mass, uncontrolled immigration.

The number of grenade attacks and car fires in the relatively small nation has shot up in recent years – allegedly because of warring migrant gangs – and the number of fatal shootings has doubled in nine years.

Since Mr. Trump made his intervention in February, Stockholm and Malmö have experienced grenade attacks, there have been shootings and riots in the No-Go Zone of Rinkeby in Stockholm, and ambulance workers have demanded “military” defence gear so they can enter the area.