By Fang Yan and Matthew Miller

Chinese construction gear maker Zoomlion Heavy Industry Science and Technology Co Ltd has denied accusations it spied on rival Sany Heavy Industry Co Ltd, or was involved in the kidnapping of the son of Sany's chairman.

It was Sany's employees that were found to have tried to spy on Zoomlion and gain access to Zoomlion's computer systems in three separate cases since 2009, Zoomlion's chairman Zhan Chunxin said in a filing to the Hong Kong stock exchange late on Monday, citing separate police investigations and the company's own independent investigation.

Sany declined to comment.

Sany and Zoomlion, both based in Hunan province in central China, have been competing fiercely for a bigger share of the construction equipment market. The rivalry has escalated to a public row since late last year amid a slowdown in the market.

Zoomlion said in its statement that it was not involved in the kidnapping of Liang Zaizhong, son of Sany chairman Liang Wengeng, as Liang had claimed in an recent interview with a local media.

The company also was not involved in the detention of Liang Zaizhong's assistant by a local customs office in early 2012, Zoomlion said.

Zoomlion said it "wishes that all fictitious allegations made against the company can be put to an end."

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