Walmart filed a multi-million dollar lawsuit against Tesla on Tuesday.

The retail giant says Tesla’s "negligent installation and maintenance" of solar panels caused fires on the roofs of as many as seven Walmart stores since 2012.

Most people think of Tesla as an electric car manufacturer, but Tesla also sells other products related to renewable energy.

Since the 2016 acquisition of SolarCity, Tesla has had a substantial solar panel business.

Walmart hired SolarCity to install and manage solar panels on the roofs of more than 240 Walmart stores. Unfortunately, Walmart says, these solar installations had a habit of catching fire.