Retail chain Nordstrom Rack has apologised after employees called the police on three African-American teens shopping for prom.

The friends say they were falsely accused of shoplifting after an elderly female customer called them “punks”. A mother of one of the young men wrote on Facebook that a store manager followed the trio out of the Brentwood, Missouri store, where she said police officers “surrounded them as the manager falsely accused and reported that they had stolen ‘several items’ from the store”.

“I am appalled that my son and his friends were harassed, falsely accused and questioned for stealing when NO ONE STOLE A THING!” Twyla Lee wrote.

Nordstrom swiftly moved into damage control. The company said in a statement that staff did not follow store guidelines “that direct our employees to only call the police in emergency situations”. Nordstrom Rack president Nordstrom Rack Geevy Thomas called the families to apologise and subsequently met with them.

“I appreciate the opportunity to listen to their concerns and offer our sincere apologies on behalf of Nordstrom,” Mr Thomas said in a statement, adding that the retailer was “conducting a thorough internal investigation”.

“We are committed to ensuring our processes and guidelines are well understood by our employees, and identifying opportunities to enhance the training and resources we offer them”, he said.

But Adolphus Pruitt of the St Louis NAACP said the incident pointed to a deeper problem of entrenched bias in society, and he called on the store to offer a sustained response by funding programmes that help disadvantaged youth.

“They can choose to assist in stamping out this pervasive stereotyping that labels young black men as ‘criminal predators’ and embrace the decisions and sacrifices of these students or they can choose to do what has become the standard — apologise and initiate diversity training for its employees”, he said in a statement to the St Louis Post-Dispatch.

The incident follows a national uproar after Starbucks employees in Philadelphia called the police on two African-American, who were then escorted out of the store in handcuffs. They were released without being charged.