Stamford police are asking for the public's help and have also released a video of the attack, which was obtained through store cameras.
The three men can be seen gathering before the attack outside the Subway at 1126 E. Main St. at 9:05 p.m. All three men obscure their faces until one man bursts into the Subway and jumps behind the counter, where he knocks down and punches the clerk, police said. A second suspect enters the Subway and acts as a lookout, while the third man stands outside the Subway and also acts as a lookout, police said.
The attacker goes to the register but is frustrated in his attempts to break into it and flees after he can't pop it open, police said. The other two suspects flee as well, heading east on East Main Street, police said.
The injured clerk was transported to Stamford Hospital, where he was treated for cuts and a concussion, police said.
Anyone with information on the attempted robbery or the suspects is asked to contact Stamford Police at 203-977-4417.
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