TORONTO -- The head of the Canadian Auto Workers union is accusing Caterpillar Inc. of not following the rules in its 2010 takeover of a London, Ont. locomotive plant it has decided to shut down.

CAW national president Ken Lewenza has written a letter to Industry Minister Christian Paradis, calling on him to release the financial details of Caterpillar's takeover of Electro-Motive Canada..

The federal government has said that the takeover was never looked at by Investment Canada because it fell under the $300-million threshold.

But Lewenza says no public, independently verifiable data supports that claim and Caterpillar's own financial statement reported US$1.3 billion in assets associated with the takeover.

The American-based heavy equipment maker announced last week that it will close its Electro-Motive plant in London, Ont., a month after it locked out about 450 workers.

Lewenza says if the data associated with Caterpillar's purchase of Electro-Motive turns out to be inaccurate, the government can impose penalties, including annulling the acquisition.

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