We have directed police to proceed

Home Ministry official

An unnamed Home Ministry official told the French news agency that a Dhaka magistrate had given the police the go-ahead to investigate and, if necessary, to prosecute Mr Kabir, who is under arrest.

Mr Kabir has been in detention since 22 November, when he was detained at Dhaka airport upon his return from the Indian city of Calcutta.

The charge of treason carries a maximum penalty of death, but correspondents say that in practice those convicted are generally given long prison sentences or granted an amnesty.

Attacks 'documented'

The move to charge him with treason follows an order by the Bangladesh High Court directing the authorities to explain the reasons for his arrest.

The court said that failure to do so would result in the arrest being declared illegal.

Mr Kabir had been filming in the Indian state of West Bengal, to where hundreds of Hindu families fled after what they said were violent attacks, rape and theft of land following the general elections in October.

A campaigner against Islamic fundamentalism, he said he had previously documented evidence of attacks on the minority Hindu community by Muslim militants.

Prime Minister Khaleda Zia's coalition government - which includes two Islamic parties - acknowledged there had been some attacks

But it said that reports of widespread violence against Hindus were exaggerated.

Local media and human rights organisations view the arrest of Mr Kabir as a move to curtail the journalist's right to free speech and expression, and have demanded that he be set free.

Mr Kabir's arrest has been condemned by Amnesty International, which has also called for his release.