Demonstrators protest re-arrest of Zimbabwean rights activists, inluding Jestina Mukoko, in Harare, 5 May 2009

The Movement for Democratic Change party of Prime Minister Morgan Tsvangirai has denounced a judge's ruling revoking the bail of 18 political and human rights activists who were charged in connection with an alleged plot to overthrow President Robert Mugabe. The MDC party says the re-arrests threaten Zimbabwe's unity government. The re-arrests have shocked even the most hardened critics of Mr. Mugabe and his ZANU-PF party.

The activists were all taken into custody, mostly from their homes, beginning last October, held in secret locations, where they claim they were tortured, and finally released into police cells days before the 2008 Christmas holiday.

Not a single activist or former opposition Movement for Democratic Change leader or supporter, among tens of thousands arrested in the last ten years, has been successfully prosecuted for similar charges despite, what courts lawyers say, are overwhelmingly staffed by Mr Mugabe's loyalists.

Prime Minister Tsvangirai's MDC party warned Tuesday the re-arrests threaten the survival of the already shaky unity government.

Western diplomats and human rights activists packed Harare's decrepit Magistrate's Court Tuesday to greet and support the activists who had been freed on bail in March.

Zimbabwean human rights activist Jestina Mukoko arrives at magistrate's court in Harare, 24 Dec 2008

Among them was Zimbabwe Peace Project director Jestina Mukoko, whose abduction on December 3 and apparent injuries incurred while in custody, shocked her supporters and sparked an international outcry.

Upon learning of the re-arrests, a Western diplomat, who has been among the most supportive of the Zimbabwe unity government, said, "They have gone too far, and this is bad, perhaps terminal."

Several of the activists, including freelance journalist Shadreck Manyere, were not in court on Tuesday because they were still in the hospital being treated for injuries believed sustained during their earlier detentions.

The Movement for Democratic Change party (MDC) released a statement saying, "Today's [court] ruling seriously threatens not only the life and health of the inclusive government, but its longevity and durability." The MDC also said "the ruling slams shut the door of international goodwill."

Activists' defense lawyer Alec Muchadehama said he would appeal Tuesday's decision on revoking bail which was made by Harare Magistrate Catherine Chimanda. Other defense lawyers say they will file new bail applications. Magistrate Chimanda said the trial, involving charges of sabotage, terrorism and banditry, will begin on July 4.