THE brother of George Zimmerman, the Florida man acquitted after shooting dead an unarmed black teenager, said his family receive 400 death threats a minute.

Robert Zimmerman Jr said he and his parents have lived in constant fear since the verdict last month in the killing of Trayvon Martin provoked widespread outrage in the US.

Added to the death threats, which come via social media, Zimmerman said he has also faced threats in public and said he almost got beaten up by two Starbucks' employees.

“No one has really asked us to get into the psychological aspect of this,' he told US news website Breitbart. “You don’t know if someone stops you in public and says, "excuse me sir", you don’t know if you dropped your wallet or if someone recognizes you and wants to kill you.”

“I think the whole ordeal has taught us to rely on one another. But it taxes everyone's mind, knowing you have to stay in touch and in constant communication because of the threats.”

In spite of the apparent threat posed to him George Zimmerman has made a number of surprising appearances since his acquittal.

Two weeks ago he rescued a family-of-four from their upturned SUV in Florida, near the scene where he shot dead Martin, 17.

This week he was stopped in Texas for speeding, telling the officer who pulled him over he was carrying a gun.

“There’s a psychological toll for living in isolation for as long as we have,” Robert Zimmerman Jr told Breitbart. “I’m not sure how to learn to trust or interact with people or how to break out of that.

“My concern is that there will never be a return to normal. At best, there will be a new normal, but that will always be plagued by concern over everyone we encounter.”