Can a marketing campaign be too effective? For Build-A-Bear, finding out just how passionate its fans are turned out to be a painful learning experience on Thursday. A promotion meant to drive sales ended up driving employees to tears and law enforcement was called to quell angry crowds.

Build-A-Bear Workshop stores offer make-your-own stuffed animals for upwards of $50-$75 before add-ons. When the brand announced a one-day promotion to “pay your age” for as little as $1, shopping malls in the US, UK and Canada filled with lines—some extending outside and down the street.

In some locations, customers reported pushing, shoving and general chaos before law enforcement was called in. Guests in other time zones were turned away before the stores were scheduled to open once the company realized what was happening.

Build-A-Bear handed out $15 vouchers for those unable to take part in the promotion and issued a formal apology. The company’s CEO even went on The Today Show to ease consumer stress.

“We are doing our very best and we are staying very focused on making sure that we do the best we can to make it right for people,” Build-A-Bear CEO Price John said. “I am sorry that we were not able to provide the service that we wanted.”

Earlier this year, Nutella found itself in similar hot water when French supermarket chain Intermarché offered a steep discount that resulted in chaos.

“They were like animals. A woman had her hair pulled, an elderly lady took a box on her head, another had a bloody hand. It was horrible,” one Intermarché customer told French newspaper Le Progres.

The mob-inducing promotion was not offered by Nutella parent company Ferrero itself, but they were forced to issue a statement nonetheless.

McDonald’s also found itself facing a mob last year when it offered a limited quantity of Szechuan nugget dipping sauce. Inspired by an episode of Rick and Morty, the restaurant brought the sauce back for one day. Fans were angered when quantities quickly ran out.