Paul McCartney called on China to better regulate its so-called “wet markets” — one of which could have been the source of the COVID-19 outbreak — during an interview with Howard Stern Tuesday, according to The Hollywood Reporter. One of the earliest cases of the coronavirus was found in a delivery person who worked at the Huanan Seafood Wholesale Market in Wuhan, China. Markets like these often feature an array of live and pre-slaughtered animals for sale, and the nickname, “wet markets,” comes from the water used to wash away the mixture of animal blood, guts and other bodily fluids that inevitably spill about. This makes such spaces ripe for disease because, as Christian Walzer, executive health director of the Wildlife Conservation Society, recently told Rolling Stone, “Each animal is a package of pathogens.” McCartney, a long-time vegetarian and animal rights advocate, said he hoped the COVID-19 outbreak would force China’s hand on wet markets, saying, “I really hope that this will mean the Chinese government says, ‘OK guys, we have really got to get super hygienic around here.’” He added: “They might as well be letting off atomic bombs because it’s affecting the whole world. Whoever is responsible for this is at war with the world and itself.” In speaking out against the wet markets, however, McCartney also peddled the problematic conspiracy theory that the coronavirus originated with Chinese people eating bats, implying that the practice is commonplace. “Let’s face it, it is a little bit medieval eating bats,” McCartney told Stern, adding, “They don’t need all the people dying. And what’s it for? All these medieval practices.” As the coronavirus outbreak took hold beyond China, the “bat-eating theory” spread quickly through tabloids, conservative blogs and social media despite no hard evidence. And while COVID-19 may have originated with an animal before spreading to humans, many have spoken out against the offensive nature of pinning it specifically on a foreign country’s eating habits. “It’s not simply a matter of the consumption of exotic animals per se,” Adam Kamradt-Scott, an associate professor specializing in global health security at the University of Sydney, told Time. “So we need to be mindful of picking on or condemning cultural practices.”