One day after the US Vice-President Joe Biden dined with the Serbian President Boris Tadic at his office in Belgrade, Serbian police arrested a man who came to the office armed with two hand grenades and threatened to blow himself up at the entrance unless his court case was settled.
The man, Dragan Maric, 57, who police said was mentally disturbed, had already pulled the safety pin out of one grenade.
Police removed it from him before he could activate it, having already seized the other one.
Mr Maric had given numerous warnings that he would carry out such an attack. "He's arrested. It's over," a senior police official told Reuters. "The bomb has been safely taken away from him after five hours of negotiations."
A presidential aide, Jasmina Stojanov, said: "The man came to the entrance normally used by journalists and citizens who come to visit the building."
But he became trapped in a three-square metre sealed-off area between two entrance doors, one of them armoured, and a stand-off with police ensued.
He gave the government a 2pm deadline to respond to his request for an "out-of-court settlement" to what the media said was a property dispute, but the time passed without incident as police negotiators tried to persuade him to give himself up.
In a letter to Mr Tadic, Mr Maric said he had no intention of hurting anyone and that "death is better than the tyranny of the regime".
He said the government had stolen $1.2m (£760,000) in cash, an emerald, securities, computers and documents from him.
He claimed that he had mailed his demands to 11,000 addresses, including to European Union commissioners, the presidents of EU member states and governments, the EU, US and Russian media, the United Nations and foreign embassies in Belgrade.
"The man is a psychiatric case," another police official said.
The military analyst Aleksandar Radic said: "It is too early to analyse, but the problem is that the man told the police in advance he would do it and no one did anything to stop him."