ORLANDO, Fla. (AP) — Members of a self-described black militia group will attempt a citizen’s arrest on a white neighborhood watch leader who has admitted to fatally shooting an unarmed African-American teen in an Orlando suburb, but has not been charged, a leader of the group said Thursday.

Members of The New Black Liberation Militia plan to take 28-year-old George Zimmerman to federal authorities this week since local police haven’t acted, said Najee Muhammad, a leader of the militia group.

“We’ll find him. We’ve got his mug shot and everything,” Muhammad said.

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Sanford police did investigate but have declined for now to arrest Zimmerman who says he acted self-defense last month when he shot 17-year-old Trayvon Martin. Police say they have no evidence to disprove his assertion. They have since turned the case over to the State Attorney’s Office, and a spokeswoman said it could be weeks before a decision is made on whether to file charges or present the case to a grand jury.

An attorney for the teen’s family said they are discouraging actions such as what the militia proposed.

“They want justice at the hands of authorities and nobody else,” said attorney Benjamin Crump. “Everybody has a right to peacefully assemble but we certainly want to leave any kind of arrests … to the authorities.”

A spokesman for Sanford police didn’t return an email seeking comment about the militia group’s plans. Zimmerman has a disconnected number and couldn’t be reached for comment.

Moments before the shooting, Zimmerman had called police to report a suspicious person in the neighborhood. After a confrontation, he shot and killed Martin who was walking back from a convenience store to a house in the Sanford neighborhood where the teen’s father’s fiancée lived.

Out of a population of 54,000, about 57 percent of Sanford residents are white and 31 percent are black, according to the 2010 U.S. Census. The median income is about $43,000.

Martin’s family has criticized police for not arresting Zimmerman. They filed a lawsuit asking that the 911 tapes be released, but police have said the tapes are part of the investigation and will only be released once the State Attorney’s Office is done evaluating the case.

A spokeswoman for the Southern Poverty Law Center, a civil rights group that monitors hate groups, said her organization didn’t have any information on The New Black Liberation Militia. The group describes itself on its website as “Developing and Teaching Spiritual, Psychological, Social, Holistic and Scientific Methods and Techniques to ensure the survival of black people in the 21st century and beyond.”

Photos on the site show men dressed in fatigues and berets.

There is no mention of citizen’s arrests in Florida’s criminal statutes but state courts have cited common law in establishing when such an arrest can be made. The crime has to be a felony. It has to be witnessed by the citizen making the arrest or the citizen has to have probable cause that the person being arrested is guilty of a felony.

Orlando criminal defense attorney Patrick Cairns said members of the militia face a high legal hurdle in taking such action since they didn’t witness a crime. They could be charged with false imprisonment if they detain Zimmerman.

“You do a citizen’s arrest only if you think the cops aren’t going to get there in time and you’re afraid somebody is going to leave the scene,” Cairns said.

The family started an online petition for the State Attorney’s Office, demanding an arrest.

“Trayvon was unarmed when he was shot by Zimmerman,” said the online petition, which has been signed by almost 215,000 people. “Please uphold justice.”

Copyright 2012 The Associated Press.