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LONDON, May 6 (Reuters) - A Chinese-owned ship carrying a cache of weapons originally destined for Zimbabwe has only unloaded construction equipment in Angola and not its consignment of arms, transport unions said on Tuesday.

The International Transport Workers Federation (ITF), which has been tracking the ship's movements for weeks, said fellow trade unions in Luanda reported the An Yue Jiang unloading only cement and construction material.

Zambia, which chairs the Southern African Development Community grouping, last month urged regional states to bar the ship from entering their waters, saying the weapons could deepen Zimbabwe's election crisis.

"No attempt was made to offload any armaments and the ship sailed after taking on fuel and food," the ITF said in a statement.

"Trade unionists, including from the port workers' union, maintained a watch on the ship and what came off and went on it throughout its stay in port. The police were also present," the ITF said.

China last month said the arms shipment would be recalled after South African port workers refused to unload it and two other southern African nations denied it access to their ports.

Zimbabwe's opposition Movement for Democratic Change rejects official results of the March 29 election showing its leader Morgan Tsvangirai won with less than the outright majority need to defeat President Robert Mugabe. (Reporting by Stefano Ambrogi; Editing by Jon Boyle)

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