Cleared by a Florida jury, George Zimmerman walked free from criminal charges in the shooting death of unarmed black teenager Trayvon Martin but was still under fire from civil rights leaders and critics who were dismayed by the verdict.

Civil rights leaders in the US have demanded the arrest of a neighbourhood watch helper who went free after shooting dead an unarmed black teenager.

The head of America’s National Association for the Advancement of Coloured People said today a newspaper’s controversial dead chimp cartoon was an invitation to assassinate US President Barack Obama and urged readers to boycott the tabloid.