Police Tuesday arrested a man who allegedly assaulted a 70-year-old woman last month on an R train platform in Brooklyn.

James Showell, 54, of Bedford-Stuyvesant, was charged with assault for punching the woman while on a southbound platform of the 4th Avenue-9th Street train station on March 30 at 10:45 a.m.. There was no attempt to rob her and no statements were made before the seemingly random assault, an NYPD spokeswoman said. The woman was not hospitalized.