Police say four masked men entered a suburban Washington, D.C., jewelry store, shattered a glass display case with a hammer and made off with 23 Rolex watches worth more than $600,000.

Tuesday's heist at the Fashion Centre at northern Virginia's Pentagon City Mall took about 30 seconds. Police say the suspects fled in a car driven by a fifth person.

It was the second smash-and-grab crime reported by authorities at the mall in two months. On Feb. 4, four masked men walked into another jewelry store at the Fashion Centre, shattered a display case with hammers and made off with $128,000 in rings. The men fled in a car driven by a fifth person.

Police have not said if they believe the two crimes are related.