George Zimmerman was held in "investigative police custody" for a brief time on Monday after allegedly threatening his wife Shellie and her father with a gun at their Florida home.

According to police in Lake Mary, Zimmerman, who was acquitted in July of murdering the unarmed black teenager Trayvon Martin, was involved in a dispute during the afternoon at the house belonging to his in-laws.

"We received a 911 call that there was a domestic issue happening at the residence," said officer Zach Hudson, spokesman for the Lake Mary police department.

"The caller was Shellie. She is claiming that, according to the 911 call, that Mr Zimmerman was threatening her and her father with a weapon. She said she was being threatened with the handgun and it was threatening behaviour. We got on scene and we are now conducting an investigation."

Police later released the 911 call made by Shellie Zimmerman, 26, who filed for divorce last week to end her six-year marriage to her 29-year-old husband, acquitted on 13 July of the second-degree murder of Martin, 17, in a confrontation at his Sanford housing estate.

In the call, Shellie Zimmerman, who was convicted of perjury last month for lying about the couple's finances at her husband's bail hearing last year, said he was waving a gun at her and her father, David Dean, and also assaulted him.

"He's in his car and he continually has his hand on his gun, and he keeps saying 'step closer' and he's just threatening all of us," she said on the recording. "He punched my dad in the nose; my dad has a mark on the nose. I saw his glasses were on the floor."

She said that Zimmerman also snatched an iPad from her and smashed it before cutting it with a knife. "Dad, get inside the house – George might start shooting at us," she is heard to say on the tape.

Steve Bracknell, the Lake Mary chief of police, said later on Monday that neither Shellie Zimmerman nor Dean planned to pursue the case. "They both have declined to press charges against George. We have no victim, no crime," he said.

The incident follows claims from Zimmerman in an interview after she pleaded guilty to perjury that she was frightened of her husband, who she said had a volatile temper. She said that she felt let down by him, and that he had "beaten down my self-esteem".

According to an email to reporters on Monday afternoon from Mark O'Mara, the lawyer who secured George Zimmerman's acquittal, the couple had been living together at her father's house since the trial ended.

He said they had separated, and that they were going through some of their belongings when this afternoon's incident happened. "There was heightened emotion and a disagreement took place," O'Mara wrote.

Robert Zimmerman, George's brother and self-appointed family spokesman, sent out a tweet Monday suggesting there was more to the episode than first appeared. "We've learned from GZ case not to 'jump to conclusions', to wait for facts & avoid speculation," he wrote. "'News' is a business – not your friend," he added.

Zimmerman has been stopped for speeding twice since the trial, receiving a ticket in Lake Mary last week. He also appeared smiling with an employee at the Cocoa factory of the gun manufacturer Kel-Tec, the same brand of pistol he used to shoot Martin through the heart during their February 2012 confrontation at a Sanford gated community.

A spokesman for O'Mara's office said the visit was ill-advised.