George Zimmerman, the Florida neighborhood watchman whose shooting of an unarmed black teen triggered a national scandal, has been detained over alleged domestic violence, the Orlando Sentinel reported Monday.

Police in Lake Mary, central Florida, were looking into a "possible domestic battery" involving Zimmerman, 29, who was held and then released, the Sentinel reported.

The report cited police saying it was not immediately clear if a weapon found at the home of the parents of Zimmerman's estranged wife was used in the alleged offense.

Shellie Zimmerman filed for divorce last week.

A police spokesman did not immediately confirm the report.

But in the wife's emotional 911 call to police -- a recording of which was released on a local news website -- Shellie Zimmerman said that her estranged husband threatened her and her parents with a gun.

He is "in his car and he continually has his hand on his gun ... and and he keeps saying 'step closer,'" she said in an alarmed voice in the 911 call released by police.

"He's just threatening all of us. He's going to shoot us. ... He accosted my father, took my iPad out of my hand and smashed it ... I'm really, really afraid."

"Dad, get behind the car or something. Dad, get inside the house!" she is heard shouting, before requesting medical attention for her father. "Oh my God, Oh my God."

The police phone operator is heard trying to calm the wife, and saying that officers have been sent to the scene.

Zimmerman admitted to shooting Martin, but insisted it was in self-defense, claiming the teen had wrestled him to the ground and pounded his head against the sidewalk.

In July, a jury found Zimmerman not guilty on a charge of second-degree murder and he walked free.

The shooting happened when Zimmerman was following Martin on suspicion the 17-year-old, who was walking home from the store with a bottle of ice tea and a pack of candy, was involved in robberies in the neighborhood.

An initial decision by Florida investigators not to press charges in the case set off widespread protests, with Martin's supporters alleging racism and pointing to the fact that the teenager was unarmed and had no criminal record.

The incident was widely covered by the national media, and also ignited debate over the state's controversial "Stand Your Ground" law, which allows the use of a gun in self-defense even when it is possible to flee.