Norwegian police said on Thursday they found a kayak they believe belonged to a missing WikiLeaks associate who disappeared in mysterious circumstances three weeks ago.
Police posted a photo of a white folding kayak that they believe Dutch cybersecurity expert Arjen Kamphuis bought just before going on holiday to Norway.
Kamphuis, 47, has not been seen since he left his hotel in the northern Norwegian city of Bodo on August 20.
His disappearance has triggered a wave of conspiracy theories on social networks, ranging from the CIA and Russian participation to a mission to carry out a secret project for WikiLeaks founder, Julian Assange.
However, police said they were examining three theories: a voluntary disappearance that includes a possible suicide, an accident or a crime.
WikiLeaks, which published secret military documents and US diplomatic cables in 2010, called Kamphuis's disappearance "strange."
He said he is an associate of Assange, who has taken refuge in the Ecuadorian embassy in London since 2012 for fear of being extradited to the United States.
In a statement Thursday, police said they "still have all possibilities open to what might have happened to the missing person."
On Wednesday, they said a fisherman found some of Kamphuis' personal belongings floating in the waters some 50 kilometers east of Bodo.
The police have not clarified what the objects are due to the ongoing investigation, but the Norwegian TV2 station reported that they include Kamphuis identification documents.
The kayak was found in the same area as the objects and the police continue their search.
Kamphuis had a ticket but did not take a flight from August 22 to the Netherlands from Trondheim, a city located more than 700 kilometers south of Bodo.
A telephone linked to Kamphuis was briefly lit in an area near the city of Stavanger, located 1,600 kilometers southwest of Bodo, on August 30, police said, but could not confirm who was using it.
Her friend Ancilla van de Leest told AFP on Wednesday that Kamphuis showed no signs of being suicidal and that his links to WikiLeaks were "very exaggerated in the press."