The Ugandan High Court has ordered the police to produce a journalist who has been held in an unknown location for 13 days, after a local media watchdog sued security chiefs over his disappearance.

Though Uganda has long enjoyed more press freedom than some African countries, rights groups and reporters have accused the government of cracking down since opposition protests erupted in the capital Kampala in April.

Augustine Okello, a radio journalist, disappeared after attending a meeting he was invited to by government security operatives, according to the Human Rights Network for Journalists-Uganda (HRNJ-Uganda).

"We obtained a habeas corpus for Okello (late on Monday) and the security bosses are required to produce Okello in court within 24 hours," the association's Geoffrey Sebaggala told Reuters.

Rights groups in Uganda have resorted to habeas corpus petitions in the past in a bid to free people being held without charge by the security services.

A radio reporter seized in November 2010 and held for 10 days handcuffed in a dark room was released the day after a habeas corpus petition was filed, according to the New York-based Committee to Protect Journalists.

The police have admitted holding Okello, but he has not been charged and his lawyer and family were not told where he was being held, the group said.

The police were not immediately available for comment on the High Court order.

HRNJ-Uganda said it did not know why Okello had been arrested.

Under Ugandan law, suspects cannot be held for more than 48 hours without charge or access to a lawyer.

The group sued the chief of the defence forces, the inspector general of police and the head of military intelligence in an attempt to force the journalist's release.

Ugandan journalists imposed a news blackout on the government in April to protest against beatings and confiscation of their equipment by the police while covering demonstrations against high food and fuel prices.

President Yoweri Museveni, who has been in power for 25 years and won a disputed election in February, called local and foreign journalists "enemies" of the country in April and accused them of exaggerating the violence.

Court Human rights New York Uganda