A special prosecutor investigating the death of an unarmed black teenager in Florida invoked an exemption on Thursday that allows authorities to deny the release of otherwise public information to the media.
The national media has converged on this Orlando suburb to cover a story that has gripped the country and renewed a discussion about race relations in America. Despite this, public officials have told reporters not to bother asking questions.
"At this time, we are asserting an active criminal investigative information records exemption for any documents, videos, or factual information regarding the case," special prosecutor Angela Corey's office said in a statement.
The clampdown coincides with intense public interest in the February 26 shooting death of Trayvon Martin, 17, by neighborhood watch captain George Zimmerman, 28, whose father is white and mother is Hispanic.
Zimmerman says he fired in self-defense and police have not arrested him, citing the state's "stand your ground" law that allows people to use deadly force when they perceive danger in any public place.
The case has generated demonstrations across the country from people who want Zimmerman arrested.
Corey was appointed by Governor Rick Scott to take over the case after public confidence in the previous investigation faltered.
Her order would restrict video such as the surveillance camera images released by the city on Wednesday that showed Zimmerman arriving at the police station in handcuffs the night of the shooting.
The video showed no apparent injuries, potentially undermining Zimmerman's account that Martin punched him in the nose and repeatedly slammed the back of his head against the sidewalk.
The special prosecutor's announcement came two days after the city of Sanford stopped holding daily press conferences and said the city and the Sanford Police Department would refer all media questions to Corey's office.
On Wednesday the city went so far as to threaten to arrest reporters for stalking if they approached city employees seeking information in the case, only to rescind that threat on Thursday.