Good Stuff Eatery owner Spike Mendelsohn working the line with his crew during the lunch rush. (James M. Thresher for The Washington Post)

On Saturday night Good Stuff Eatery, the burger joint owned by celebrity chef Spike Mendelsohn and once visited by President Obama, was robbed by two men assumed to be former employees, according to a restaurant spokesperson.

The robbers, wearing ski masks and brandishing a handgun, entered through the Capitol Hill location’s back door after the restaurant’s 10 p.m. closing. The restaurant was empty of customers, and the intruders made off with about $800 cash stored in two cash registers, escaping via a dark-colored four-door sedan, according to D.C. police.

“It appears to be a former employee, who was caught on the extensive video cameras in the store and area,” wrote Sunnyside Restaurant Group spokeswoman Micheline Mendelsohn Luhn in an e-mail. Luhn, the famous chef’s sister, added that police were “extremely responsive.”

“We are thankful our closing employees are OK and the neighborhood response has been overwhelming,” Luhn wrote.