NEW YORK — Chipotle is giving away free burritos to combat the eeriness of empty stores and convince people that its food is safe.

The Denver chain made its first big push with freebies Feb. 8 when it closed stores nationwide for a few hours so employees could participate in a food safety meeting after an E. Coli outbreak and other incidents sent sales plunging.

The company said 5.3 million people tried to download the mobile coupon for a free entree offered that day as a “rain check” for when stores were closed.

“That was our first test to see how much people really wanted to come back to Chipotle,” said Mark Crumpacker, chief creative and development officer, speaking Wednesday at the Bank of America Merrill Lynch Consumer and Retail Tech Conference.

The company has since also started mailing people coupons for a free entree. Crumpacker said there are about 6 to 10 million such offers in circulation already, out of the 21 million the company has planned. Those all expire by around May 15, he said.

Moving into the summer, he said Chipotle might shift to “Buy One, Get One” free offers or do more targeted mobile offers for free meals in regions of the country where a recovery in sales is lagging.

It may seem like a desperate measure to get people back in stores, but Crumpacker said the expiration dates on coupons give people that extra nudge they might need to go into a Chipotle again. Executives are concerned about the perception customers may have when they see empty restaurants.

Chipotle had become a star on Wall Street, with its restaurants packed and its sales booming.