Slovak Prime Minister Robert Fico suffered life-threatening injuries when he was shot and wounded in an attempted assassination on Wednesday, the government office said,
Reuters reports.
Slovak media said the shooter was a 71-year-old man but the motive was not immediately clear.
The incident shocked Slovakia, a small central European nation with little history of political violence. Slovakia's partners in the European Union and NATO condemned the shooting.
Fico, 59, was rushed to hospital in the central Slovak town of Handlova where he had been chairing a government meeting. He was then transported by helicopter to regional capital Banska Bystrica for urgent treatment, it said, adding that his condition was too serious for him to be taken to Bratislava.
A Reuters witness heard three or four shots as Fico exited a building to shake hands with a crowd of people who had been waiting to greet him. Police then wrestled a man to the ground.
"An assassination (attempt) on Prime Minister Robert Fico was carried out today at the government's off-site meeting in Handlova," the government office said in a statement.
News outlet Aktuality.sk reported the shooter was a 71-year-old man and cited his son as saying his father was the legal holder of a gun licence. It did not name either of the men.
"I have absolutely no idea what my father intended, what he planned, what happened," it quoted the shooter's son as saying.
Broadcaster TA3 reported four shots had been fired, and that the leftist prime minister had been hit in the abdomen.
"I don't think I will wake up from this," Lubica Valkova, a 66-year-old resident told reporters. "This kind of thing just can't happen in Slovakia."