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KABUL, May 13 (Reuters) - The Taliban's top operational commander, Mullah Dadullah, has been killed in a clash in Afghanistan, security officials said on Sunday.

"Mullah Dadullah has been killed and his body is in Kandahar," said Saeed Ansari, spokesman for the intelligence department.

Another intelligence official said the one-legged Dadullah was killed in a clash with Afghan troops in the southern province of Helmand on Saturday night.

Apart from leading most Taliban attacks in the south, the notorious Dadullah was also believed to be behind a series of kidnappings of foreigners and Afghans.

There have been several reports over recent years that Dadullah had been killed or captured.

If confirmed, his death would be a heavy blow for the Taliban, fighting to expel foreign troops since they were ousted in a U.S.-led offensive after the Sept. 11, 2001, attacks.

He would also be the most important Taliban killed since then.

In December, U.S.-led forces killed another top Taliban official, Mullah Mohammad Akhtar Osmani, in an air attack in the south of the country after a tip-off by Pakistan.

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