Bahraini authorities arrested a former photographer for Agence France-Presse on unspecified charges on his return from a holiday abroad, the French news agency reported.

Mohammed Al-Shaikh, a prize-winning local photojournalist who worked for AFP in Bahrain for several years, was detained at Manama airport late on Tuesday, AFP and the UK-based Bahrain Press Association, which seeks to defend journalists in the Gulf Arab state, said late Wednesday.

AFP management expressed its "most serious concern" for the journalist's well-being and called on Bahraini authorities to explain as soon as possible why he had been detained, the agency said.

The authorities did not immediately respond to a Reuters request for comment.

Al-Shaikh won the 2014 Bayeux-Calvados prize for his coverage of an uprising in the Gulf island monarchy in 2011 which was put down by the authorities with help from several other Gulf Arab states.

AFP said Al-Shaikh's accreditation expired in August last year and authorities did not renew it, putting an end to his Bahrain coverage after more than four years with the agency.

Human rights groups say Bahrain, a strategic island that is home to the U.S. Navy's Fifth Fleet, has carried out a wide crackdown on dissent since the uprising led by the country's majority Shi'ites to demand a greater role in government.

Bahrain says its actions are directed against people who foment violence and sectarian tensions in the kingdom, denying charges by activists that it is targeting journalists and dissidents.