Norwegian police said on Friday they have ended a year-long probe into the disappearance of a Dutch cybersecurity expert, concluding he "most likely" died in an accident.

Arjen Kamphuis was last seen on August 20, 2018, when checking out from a hotel in Bodoe, just north of the Arctic Circle. A few days later, a kayak with a hole in the hull and an oar were found on the shore of the fjord, as well as some other personal items.

Those circumstances and his work, which involved advising governments, firms, journalists and activists groups on how to prevent hacking attacks, fueled speculation of possible foul play.

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Outspoken privacy campaigner

One of his clients was the anti-secrecy organization WikiLeaks.

Police said they had probed three main lines of inquiry, including that Kamphuis died in an accident, due to a crime or had deliberately decided to go into hiding.

They concluded that "Kamphuis most likely suffered an accident in the evening of August 20, 2018, while kayaking in the Skjerstad Fjord," near the village of Rognan, a police statement read.

They said his body has still not been recovered.

Many conspiracy theories

Kamphuis' disappearance triggered a wave of conspiracy theories on social media, ranging from CIA and Russian involvement to a mission to carry out a secret project for WikiLeaks founder Julian Assange.

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The mystery deepened when a phone linked to Kamphuis was briefly switched on in an area near the southwestern Norwegian city of Stavanger, located 1,600 kilometers from Bodo, on August 30 last year.

Police explained that two truck drivers from eastern Europe had found the phone, a laptop and other items belonging to Kamphuis while they were fishing close to where his kayak was found.

The pair were not believed to have any involvement in the disappearance, police said.

mm/aw (AFP, AP, dpa)

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