George Zimmerman, the man cleared of murdering unarmed teenager Trayvon Martin, has been charged with stalking.

The 34-year-old is accused of harassing and threatening Dennis Warren, a private investigator hired to work on a Jay-Z-produced documentary series about Trayvon’s life.

Police said Mr Zimmerman called Mr Warren 55 times, left 36 voicemails, sent 67 texts and 27 emails over a period of nine days in December. He also allegedly threatened the investigator with being “on his way to the inside of a gator”.

Texts sent to Mr Warren included messages such as “Answer your phone (expletive)" and “Text me again. I'll show up at your home you (expletive),” according to Florida’s Seminole County Sheriff’s Office.

Voicemails left by Mr Zimmerman featured ticking sounds that would slowly increase in frequency and speed, WKMG-TV reported.

Rest in Power: The Trayvon Martin Story, which is set to air this summer, delves into Trayvon’s death in 2012, and the impact it had on US society.

George Zimmerman: I bear a grudge against Obama

Mr Zimmerman, who was a neighbourhood watch captain in a gated community in Sanford, Florida, shot dead the 17-year-old after telling a 911 dispatcher he looked like a “real suspicious guy”.

Police initially failed to arrest Mr Zimmerman after he said he acted in self-defence, but he was later charged with murder following a public outcry. A jury found him not guilty.

Mr Zimmerman was also arrested on suspicion of domestic violence in 2015, but was not charged after the alleged victim withdrew her claims.

In pictures: Protests over the verdict in the trial of George Zimmerman Show all 7 1 /7 In pictures: Protests over the verdict in the trial of George Zimmerman In pictures: Protests over the verdict in the trial of George Zimmerman Martin1.jpg Demonstrators at a rally for Trayvon Martin at Union Square in New York (Peter Foley/EPA) In pictures: Protests over the verdict in the trial of George Zimmerman Martin2.jpg Demonstrators chant as they march through the streets of Atlanta (David Goldman/AP) In pictures: Protests over the verdict in the trial of George Zimmerman Martin3.jpg A demonstrator wears a hoodie during a protest in Atlanta (David Goldman/AP) In pictures: Protests over the verdict in the trial of George Zimmerman Martin6.jpg Police officers work to extinguish a fire during a protest n Oakland, California early on Sunday morning (Anda Chu/AP) In pictures: Protests over the verdict in the trial of George Zimmerman Martin7.jpg A demonstrator talks with police officers as people gather in Los Angeles (Jason Redmond/Reuters) In pictures: Protests over the verdict in the trial of George Zimmerman Martin4.jpg Vistors view a shrine which honors Trayvon Martin in Goldsboro, Sanford, Florida (Scott Olson/Getty Images) In pictures: Protests over the verdict in the trial of George Zimmerman Martin5.jpg Worshippers at the Middle Collegiate Church hold prayer services wearing hoodies in New York (Keith Bedford/Reuters)

He triggered further outrage in 2016 when he auctioned the gun he claimed was used to kill Trayvon for $250,000 (£184,000).