Amazon says that has suspended thousands of seller accounts for price gouging during the coronavirus pandemic.

The operator of the largest U.S. online marketplace says it has pulled well over half a million offers and suspended more than 3,900 selling accounts in the U.S. for violating its fair-pricing policies.

Amazon says it is deploying a dedicated team to identify and investigate “unfairly priced” products that are in high demand, such as protective masks and hand sanitizer.

“We are also proactively sharing information with state attorneys general and federal regulators about sellers we suspect have engaged in egregious price gouging of products related to the COVID-19 crisis,” the company said in a statement Monday.

Since the coronavirus outbreak escalated in the U.S., there have been runs on hand sanitizer, toilet paper, bleach wipes, meat and canned soup, among other products. Some people have attempted to sell cleaning products and other supplies at inflated prices on Amazon, eBay and other sites.

President Donald Trump signed an executive order on Monday to prevent hoarding and price increases of supplies.

—Bloomberg News