3 men caught on camera violently robbing woman in the Bronx

The NYPD has released surveillance video of three men violently robbing a woman in the Bronx. 
Police say the suspects approached the 25-year-old victim on East 170th Street back on Aug. 18 and began punching her in the face. 
One of the men then stole her cellphone as the others attempted to take her purse. 
All three suspects are described as being African-American. At least one is believed to be in his late teens.