Originally published at Yahoo News 

The FBI is considering hate crime charges against George Zimmerman, the Florida neighborhood watch volunteer who shot and killed unarmed black teen Trayvon Martin in February. If charged with a federal hate crime and convicted, Zimmerman could face the death penalty.

WFTV reports that Florida state prosecutors claim Zimmerman racially profiled and stalked 17-year-old Trayvon Martin in a gated community in Sanford on Feb. 26 before shooting him to death. Those allegations are the basis for the FBI’s hate crime probe.

FBI investigators are interviewing witnesses in the neighborhood where Martin was shot, looking for evidence to bolster their case for federal charges.

Zimmerman, who has pleaded not guilty to second-degree murder charges in the case, claims he shot Martin in self-defense after calling 911 to report a suspicious person in the neighborhood. Sanford police officials told the Orlando Sentinel that Zimmerman said Martin attacked him as he returned to his SUV after being instructed not to follow the teen, knocking him down and smashing his head into the ground.

On Tuesday, ABC News reported that Zimmerman’s medical report showed a broken nose, black eyes and multiple lacerations to the head the day after he shot Martin.

Also on Tuesday, the Boston Herald revealed that the gun used to shoot Martin, a Kel-Tec 9mm PF-9, is designed for self-defense.

But Martin’s family claims that the unarmed teen, who was walking in the gated Sanford community while visiting his father and his fiancé the night he was killed, was targeted because he was black. Sybrina Fulton, Martin’s mother, told MSNBC that “George Zimmerman stalked my son and murdered him in cold blood.”

Many legal observers say it will be hard enough to convict Zimmerman of second-degree murder, let alone a federal hate crime.

“What the government would have to prove is that Mr. Zimmerman acted out of hatred toward African-Americans,” WFTV legal analyst Bill Sheaffer said. “That’s why he came into contact with him. That’s why he shot and killed him.”

A photograph shown on CNN showing what is reportedly Zimmerman’s black grandfather could figure in the case as his defense team tries to prove he harbors no animosity toward blacks, as could the fact that Zimmerman and his wife mentored two black children for free and risked their safety to travel to the dangerous neighborhood where the children lived.

In other related news, CNN reports that prosecutors in the case released a summary of the evidence against Zimmerman on Tuesday, including a list of 50 possible law enforcement and 28 potential civilian witnesses, including Martin’s father, mother and brother and Zimmerman’s father and two friends. The other 22 civilian witnesses’ names were redacted.