Walmart has accused Tesla of “widespread, systemic negligence” in a lawsuit alleging the company’s solar panels are to blame for seven rooftop fires between 2012 and 2018, according to court documents cited by The New York Times. The lawsuit seeks unspecified damages for alleged breach of contract and claims that Tesla “failed to abide by prudent industry practices in installing, operating and maintaining its solar systems.” Walmart alleges that Tesla regularly sent individuals to inspect the solar systems “who lacked basic solar training and knowledge,” that the company failed to ground its solar and electrical systems properly, and that the solar panels had a number of visible defects.

The complaint said that the solar panels were installed on over 200 Walmart stores across the United States. Walmart is also seeking the removal of all of Tesla’s solar power systems from its stores. Tesla’s stock has since dropped over 1 percent. Walmart and Tesla wrote a joint statement surrounding the lawsuit: “Walmart and Tesla look forward to addressing all issues and re-energizing Tesla solar installations at Walmart stores, once all parties are certain that all concerns have been addressed. Together, we look forward to pursuing our mutual goal of a sustainable energy future. Above all else, both companies want each and every system to operate reliably, efficiently, and safely.”