Online classifieds site says the minority owner is illegally competing with its own auction site and claims it was marketed as a ‘Craigslist killer.’

Craigslist is countersuing its minority owner, eBay Inc., alleging it is competing illegally, infringing on their trademark and breaching its duty to shareholders.

Craigslist filed its complaint in Superior Court in San Francisco on Tuesday. It claims eBay broke laws by taking a series of actions in relation to its own classifieds site Kijiji, which launched last year in the United States. Craigslist claims in the lawsuit that eBay calls Kijiji the “Craigslist killer.”

EBay (EBAY, Fortune 500) sued Craigslist in April alleging Craigslist founder Craig Newmark and Chief Executive Jim Buckmaster engaged in a series of “clandestine transactions” intended to dilute its stake unfairly.