Malaysia's top court on Wednesday refused to free five ethnic Indian leaders detained indefinitely under a draconian security law, dashing hopes of the community which has been campaigning for their release.

Dismissing an appeal of the five leaders of Hindu Rights Action Force (Hindraf), held for organising a massive rally of ethnic Indians to protest their alleged marginalisation, the Federal Court held the detention as lawful.

The court's three-man panel led by Chief Judge of Malaya Alauddin Mohd Sheriff said Prime Minister Abdullah Ahmad Badawi in his capacity as the then internal security minister had rightly issued the detention order and had complied with the procedural requirements under the Internal Security Act.

The bench unanimously upheld the high court's decision to quash the leaders' habeas corpus application seeking release from detention under ISA. The act allows indefinite detention without trial.

The Hindraf five -- lawyers M Manoharan, 46, who has been recently elected a state assembly member, P Uthayakumar, 46, V Ganabatirau, 34, R. Kengadharan, 40, and Hindraf coordinator T Vasantha Kumar -- were represented by lawyer and opposition

Democratic Action Party leader Karpal Singh who said he would file for a review petition against the ruling on Monday. The respondents were represented by Attorney-General Abdul Gani Patail.

Family members and relatives of the five were present at the Federal Court. Several were seen sobbing after the decision, media reports said.

The five were detained in December last year for organising the rally, declared "illegal" by the authorities, in November.

Last week, Hindraf supporters had appealed to the home minister to send Uttayakumar to the National Heart Hospital claiming that the Hindraf leader's health was not good.

On Monday, Uttayakumar's mother too appealed to the prime minister to ensure that her son was sent to hospital for treatment.

Indian dissatisfaction over alleged discrimination is seen as one of the contributing factors to the ruling Barisan Nasional coalition's poor performance in March general elections, when it lost its two-thirds majority in Parliament.

Indians make up nearly eight per cent of Malaysia's 27 million people. Muslim Malays account for 60 per cent of the population, while ethnic Chinese make up 25 per cent.

Ethnic Indians and Chinese complain that they get fewer opportunities in education, business and jobs than the majority Malays.