About 500 people have demonstrated in Wichita over the shooting death of an unarmed black teenager by a neighborhood watch captain in Florida.

The Wichita Eagle reported that the hastily organized protest started Friday with about 250 people. The crowd grew as passers-by parked and joined the demonstration to call for repeal of a Kansas stand-your-ground law that’s based on the one in Florida.

The statute has been in the news since 17-year-old Trayvon Martin was shot Feb. 26 in the Florida town of Sanford. George Zimmerman, a neighborhood crime-watch captain, has claimed self-defense and has not been charged in the shooting.

State and federal authorities are investigating.

State Rep. Melody McCray-Miller and Sen. Oletha Faust-Goudeau were among the marchers. The Wichita Democrats expressed concerns about the stand-your-ground law.