The Rev. Al Sharpton's National Action Network organized the events following last Saturday's verdict in Sanford, Fla., in which six jurors accepted Zimmerman's claim of self-defense during a scuffle with Martin in Feb. 2012.
Trayvon Martin's mother, Sybrina Fulton, attended the event in New York, where Sharpton called on those gathered to create a new, peaceful movement for change, reports NPR's Dan Bobkoff.
"Not only do I vow to you to do what i can for Trayvon Martin, I promise you I will work hard for your children too because it's important," Fulton told the crowd.
Sharpton said he wants to fight Florida's 'Stand Your Ground' laws and for the Department of Justice to pursue civil rights charges against George Zimmerman.
