Zimbabwe's political opposition is calling on the United Nations to intervene to help end the post-election crisis gripping the nation.  From U.N. headquarters in New York, VOA's Margaret Besheer has more.

Secretary-general of the opposition Movement for Democratic Change (MDC), Tendai Biti, told reporters at the United Nations Tuesday his country has become a "war zone".

He said pro-government militias have been deployed in every district, thousands of families have been displaced, homes and farms have been burned, torture camps have been set up, people have disappeared and his party can confirm that at least 18 people have been killed since the contested presidential election on March 29.

"There is a systematic violence being unleashed by the State against the people of Zimbabwe," he said.

He called on the U.N. Security Council to adopt a "strong and decisive" resolution against the regime in Harare, and he urged the secretary-general to send a special envoy to assess the situation.

On March 29, Zimbabwe held both parliamentary and presidential elections. The MDC won control of parliament in that vote, but the results of the presidential ballot still have not been released. The opposition says its candidate, Morgan Tsvangirai won outright, but others contend a run-off vote may be necessary.

The Southern African Development Community (SADC), with South Africa in the lead, has been trying to mediate an end to the crisis. But Biti is unsatisfied with the regional response.

"It appears beyond doubt that the region itself is in a paralysis of action, and that paralysis is arising primarily because within the SADC itself, there are clearly those that are fighting in corner of people of Zimbabwe, but sadly, there are those one or two who are trying defend the status quo," he added.

Tuesday, the U.N. Security Council held a closed-door session on Zimbabwe.  Biti was not in the meeting, but said he planned to meet privately with individual ambassadors from the council's 15 countries.

The council is divided on the crisis, with some nations, including the United States, Britain and France, pressing for tougher measures against the regime of President Robert Mugabe, while some other members are resisting, saying the issue is an internal one for Zimbabwe to solve.