Probable hold-up at Duane Reade (7th Flatbush)

Today morning as I walked towards the train station, I saw police activity at the Duane Reade (7th and Flatbush Ave.) The doors were closed and a few customers had gathered outside. One of the cashiers - a young woman - was also upside speaking with the police. She looked as if someone had hit her in the face. The onlookers were talking about seeing at least two males leaving the store running.

Anyone has information as to what exactly happened?