A British man has been arrested in Somalia's semi-autonomous Puntland region, accused of illegally collecting mineral samples.
He is being held alongside a Frenchman, who faces the same charge, in the main city of Garowe while investigations continue, say officials.
The two men were arrested on Thursday after a three-month investigation into Oversight International, the company they work for, according to officials.
Two Somali staff members have also been arrested.
Puntland Security Minister Khalif Isse Mudan said: "Oversight International engaged in the illegal activity of collecting mineral samples without permission of Puntland Government."
Mr Mudan also accused Oversight International of "sharing classified information with foreign entities". He did not elaborate.
On its website, Oversight International describes itself as a Puntland-focused consultancy firm and said it is "allowed and registered as a Private Security Company with the Government of the State of Puntland".
A Foreign Office spokesman said: "We are aware of reports of the detention of a British national in Somalia (Puntland) and we are in touch with the Somali (Puntland) authorities."
Somalia has been without a strong central government since the fall of the regime of president Siad Barre in 1991.
Puntland, situated on the Horn of Africa in Somalia's northeast, declared full autonomy in 1998 but has stopped short of declaring full independence like its neighbouring region Somaliland.
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