(CNN) -- Florida's state attorney released FBI reports Thursday that may shed light on whether race played a role the night George Zimmerman shot and killed an unarmed teen.
The investigative reports are amid evidence in the second-degree murder case released by Special Prosecutor Angela Corey to Zimmerman's attorney.
The U.S. Department of Justice took up a civil rights investigation following allegations that race played a part in the killing of Trayvon Martin, 17, in February in a gated community in Sanford, Florida.
An official conclusion in the Justice Department's investigation is not expected as part of the evidence release, though details about some of the interviews will be turned over to Zimmerman's attorney.
Martin's family and supporters say Zimmerman racially profiled the teen, describing him as "suspicious" during a 911 call and ignoring a police dispatcher's request that he not follow him.
The 28-year-old neighborhood watch volunteer, who is charged with second-degree murder in the shooting, has said he killed Martin in self-defense, saying the teen punched him and slammed his head into a sidewalk before the shooting, according to family members and police.
Among the evidence released Thursday are details about federal interviews with more than 30 people, including key members of the Sanford Police Department and Zimmerman's friends, according to court documents.
The evidence also included audio of conversations between 911 dispatchers and Sanford police.
The dispatcher tells officers to look for a "black male, late teens, wearing a dark gray hoodie and sweatpants, walking around," adding that the youth was last seen running toward the back of the neighborhood.
Then, says the dispatcher, "There's screaming and a gunshot, are you responding?" Dispatchers later tell responding officers they have received a total of four calls regarding the incident. "Someone's laying in the backyard," a dispatcher says.
"I need somebody ASAP," an officer says on the recording. "I've got one down with a gunshot wound, and I've got one secure."
Also expected released were details about interviews with agents of the Florida Division of Alcoholic Beverages and Tobacco, who arrested Zimmerman in 2005 on suspicion of battery against a law enforcement officer and obstruction of justice.
The charges against Zimmerman, who was accused of pushing an undercover agent, were later dropped after he entered a pretrial diversion program and completed an anger management class.
Additionally, according to the court filings, details about Zimmerman's MySpace account, surveillance video and e-mails between Zimmerman and ousted Sanford Police Chief Bill Lee will be released as part of the evidence handover.
Zimmerman was released on $1 million bond last week. An initial bond of $150,000 was revoked last month after a judge learned that Zimmerman and his wife failed to disclose more than $150,000 in donations from the public.