Supporters of a Brooklyn father whose teenaged son was gunned down by the NYPD 20 years ago rallied outside the Brooklyn District Attorney's Office Tuesday as he met with officials.

In 1994, a housing officer reportedly mistook the toy gun that 13-year-old Nicholas Heyward Jr. was carrying for a real one and shot him dead. The teen was playing "cops and robbers" with other children in the stairwell at the Gowanus Houses.

The officer was never charged.

Nicholas Heyward Sr., the victim's father, met with representatives from the district attorney's civil rights division Tuesday.

He says that he was told prosecutors will conduct a new investigation.