The authorities in The Gambia have shut down a popular radio station critical of long-serving ruler Yahya Jammeh.

Intelligence agents ordered Teranga FM's closure without giving reasons, said Emil Touray, the head of the Gambia Press Union.

This is the first sign of a crackdown on the media since Mr Jammeh rejected defeat in the 1 December poll.

Mr Jammeh first seized power in a bloodless coup in 1994.

He initially conceded to property developer Adama Barrow, but then launched court action to annul the result, saying the poll was marred by irregularities.

The electoral commission said the poll was free and fair.

Four National Intelligence Agency operatives and a police officer visited the offices of Teranga FM on Sunday to demand its closure, a staff member told AFP on condition of anonymity.

There has been no official comment from the government.

'Climate of terror'

Station manager Alagie Ceesay was arrested in July 2015 on charges of sedition and "publication of false news" - allegations he denied.

The Gambia ranked 145 out of 180 countries in media campaign group Reporters Without Borders' 2016 World Press Freedom Index.

It said there was "a climate of terror around anything remotely to do with journalism".

The UN and West African regional body Ecowas have urged Mr Jammeh to respect the will of the people and step down when his term ends.

Ecowas officials say that neighbouring Senegal's troops are ready to intervene if Mr Jammeh refuses to hand power to Mr Barrow on 19 January.

Mr Jammeh said that any deployment would be an "act of war".

Mr Barrow caused a major upset by defeating Mr Jammeh by 43.3% to 39.6%.

The Gambia has not had a smooth transfer of power since independence from Britain in 1965.

It is a popular tourist destination because of its beaches.