An explosive device was found in a mail box outside the New York residence of billionaire financier and philanthropist George Soros, police said.
Bomb squad technicians detonated the device in a nearby wooded area, according to the New York Times, after Soros was hit by a "hostile media campaign" by the government in his native Hungary.
FBI agents and police responded to the home in Katonah, New York, after receiving a call about a suspicious package at about 3.45 pm, the Town of Bedford Police Department said in a statement.
An employee at the residence opened the package, revealing what appeared to be an explosive device.
The employee put the package in a wooded area and called authorities, police said.
Bomb squad technicians arrived and detonated it, a police official told the New York Times.
Online records showed that Soros resides at the address. He was not home at the time, the New York Times reported.
Neither local nor federal authorities would say whether the object was capable of exploding when quizzed by the press, but said the object "appeared to be an explosive".
An employee of the residence opened the package, Bedford Police Department said.
Beford police added that the FBI's terrorism task force was investigating.
Mr Soros made his fortune in hedge funds, and has donated heavily to liberal causes including an anti-Brexit campaign. He has long been a hate target for right-wing campaigners in eastern Europe and the US.
