Police in Saint John are looking for a suspect after a 75-year-old woman was mugged for her purse Saturday night.    

It happened at around 8:15 p.m. on Leinster Street.  

Police say her attacker approached her from behind and knocked her down before running away with her purse.

Right now investigators don't have much to go on except a vague description of the suspect, believed to be in his twenties.

The woman suffered minor injuries.