A prosecutor says she will not hold a hearing to determine if a Florida neighbourhood watchman should be tried for shooting dead unarmed black teenager Trayvon Martin. Angela Corey says her office is still investigating the incident. She could file charges or drop the case. George Zimmerman gunned down the 17-year-old during a confrontation at a gated community in Sanford, Florida. Mr Zimmerman, 28, claims the shooting in February was a case of self-defence. Police in Sanford have refused to arrest Mr Zimmerman, saying they found no evidence to contradict his account. Florida's self-defence law, known as "stand your ground", grants individuals scope to use deadly force if they feel seriously in danger. The case has attracted national attention, leading to protests around the US and a debate about race - Mr Martin was black while Mr Zimmerman is the son of a white father and Hispanic mother. New protest Ms Corey said in a statement that a grand jury - a panel of 25 civilians who establish if there is enough evidence in a case to proceed to trial - would not consider the Trayvon Martin shooting. "At this time, the investigation continues," the statement said. The special prosecutor said her decision to rule out a grand jury had no bearing on whether any charges would be brought. Ms Corey took over after state prosecutor Norm Wolfinger removed himself from the case last month amid criticism of the investigation. Sanford police chief Bill Lee also stepped down the same day. Mr Wolfinger had previously said a grand jury would begin considering the case this month. Mr Zimmerman's relatives say he was attacked by Mr Martin and feared for his life. The neighbourhood watchman had a permit for the 9mm handgun he was carrying on the day of the shooting. Mr Zimmerman has created a website to raise funds to cover his legal and living expenses, the Reuters news agency reports. "I was involved in a life-altering event which led me to become the subject of intense media coverage," Mr Zimmerman says on the home page. "As a result of the incident and subsequent media coverage, I have been forced to leave my home, my school, my employer, my family and ultimately, my entire life." The statement is one of the first publicly available comments from Mr Zimmerman since he went into hiding after the shooting on 26 February. On Monday, the latest in a series of protests took place in front of Sanford police department building. Police temporarily closed the police station to the public, moving some services to the city clerk's office.