COPENHAGEN, Denmark — Police in Norway are investigating the case of a missing Dutch cybersecurity expert who had worked for the anti-secrecy organization WikiLeaks.

Arjen Kamphuis was last seen on Aug. 20 when checking out from a hotel in Bodoe, just north of the Arctic Circle.

Police in northern Norway say they believe they have located Arjen Kamphuis's phone more than 1,000 kilometers (621 miles) south of Bodoe, where he was holidaying.

Police say they cannot be sure the phone was operated by Kamphuis, but that was one of several theories being investigated.

Police says telecommunication data established it had been registered on Aug. 30 in Stavanger.