By Tansa Musa

Yaounde - Police raided a TV station in Cameroon this week and shut it down, its owner said, raising fears of a media crackdown as President Paul Biya considers changing the constitution to extend his 25-year rule.

The Communications Ministry said in a statement on Friday Equinoxe TV had been closed for broadcasting illegally. A senior ministry official told Reuters the decision was linked to the station's coverage of opposition to extending Biya's rule.

"I was very shocked when a group of over 30 gendarmes and policemen stormed our television station on Thursday," said Equinoxe TV owner Severin Tchounkeu.

Journalists at state broadcaster CRTV told Reuters they had been instructed not to cover criticism of constitutional change, and last week a senior CRTV radio presenter was suspended for airing a song lambasting African leaders who cling to power.

The oil-producing central African country's constitution requires Biya, who was 75 on February 13, to step down in 2011.

But Biya said in his New Year message last month that his government would "re-examine" the constitution after what he said were popular calls for him to stay on past 2011.

Biya's party won an overwhelming parliamentary majority last year in elections the opposition dismissed as a sham, which could allow it to change the constitution.

Earlier this month, Equinoxe broadcast an interview with John Fru Ndi, leader of the main opposition Social Democratic Front, in which he accused Biya of wanting to rule for life and demanded a broad-based constitutional conference.

The station later aired footage of security forces beating SDF supporters during a demonstration against Biya.

The senior Communications Ministry official, who declined to be named, said Equinoxe's coverage of the demonstration was a major factor in the decision to shut the station.

Equinoxe is one of about 30 private radio and television stations in Cameroon who are operating without a broadcasting licence while media authorities consider their applications.

Stations are generally allowed to continue broadcasting during the lengthy application process under what the authorities have termed "administrative tolerance".

"What they call 'administrative tolerance' is simply a way to hold a sword of Damocles over the heads of private broadcasters, which they could bring down any time a broadcaster no longer serves their purposes," said Pius Njawe, general manager of Free Media Group, publisher of independent daily newspaper Le Messager and owner of Freedom Radio FM.

"I think this is a setback for press freedom."

Equinoxe's Tchounkeu said the closure came without warning.

"Since we started operating over one year ago, we have not received any complaints from the authorities of any wrong-doing. So I am confused as to why our TV station was singled out for punishment," he said.

State broadcaster CRTV has banned a critical song by Cameroonian singer Longue Longue and last week it indefinitely suspended Billy Carson, a radio presenter with the broadcaster for over 20 years, for airing the song, "50 years in power".

"Fifty years in power, that's the African disease. ... We don't want that any more," Longue Longue sings in the song.