An association of lawyers in Nepal has taken four of the most powerful men in the country to court, alleging they have flouted the law by ordering the arrest of a student leader the court had asked the government to release.

The two deputies of King Gyanendra - Tulsi Giri and Kiri Nidhi Bista, who are vice-chairmen of the council of ministers - as well as Home Minister Dan Bahadur Shahi and police chief Shyam Bhakta Thapa have been sued by the Nepal Bar Association (NBA), a body of independent lawyers.

The Supreme Court had last week ordered the government to release two student leaders, Rajendra Rai and Rup Narayan Shrestha who were arrested in the Feb 1 royal coup, after lawyers took up their case.

The two leaders were freed in the Kathmandu district court Monday but immediately after that, police tried to re-arrest them. While Rai was dragged into a waiting police van, security forces failed to get Shrestha, who was spirited away by the NBA. The two student leaders are affiliated to the student union of the largest communist party in the kingdom, the Communist Party of Nepal-Unified Marxist Leninist.

Urging Rai's release, the NBA Wednesday filed a contempt of court petition against the four top officials.

The apex court is scheduled to hear the case Thursday.

The law suit comes even as Nepal's Chief Justice Hari Prasad Sharma Wednesday summoned the home minister to his office.

The summons came after a spate of re-arrests by the government, making a mockery of the Supreme Court that had been ordering the release of several political detainees.

Lawyers say the royal takeover has crippled the functioning of the judiciary. Either the courts are not willing to admit cases against the authorities or the government has been defying court orders regarding detainees.

The chief justice himself was at the centre of a raging controversy after he attended a conference of legal experts in Australia where he supported the royal takeover.

The government Wednesday released a dozen senior political leaders following court orders.