In less than 30 seconds, the masked men in the video use a sledgehammer to smash display cases and stuff trays with “a large amount of high quality diamond jewelry” into a bag, according to the NYPD. Police said they fled with about $2.15 million worth of jewelry. The four men fled on foot and no one was injured in the robbery, the release said. The NYPD said they believe the men are in their 20s. Police said the man, who held the door open for others, fell over an employee. The NYPD is investigating the robbery, police said. Crime Stoppers is offering a reward of up to $3,500 for information leading to an arrest and indictment in the case, according to a tweet from NYPD Crime Stoppers. CNN has reached out to Rocco’s Jewelry for comment.