Slovak Prime Minister Robert Fico on Thursday was speaking but tired and still in a “really difficult condition” a day after being shot multiple times, the president-elect said after visiting his ally.

“He is able to speak but only a few sentences and then he is really, really tired … The situation is very critical,” President-elect Peter Pellegrini told reporters outside the hospital.

Surgeons spent hours in the operating theatre, battling to save the 59-year-old leader after the shooting, which happened on Wednesday afternoon as Fico spoke to members of the public after a meeting.

Footage of events just after the shooting showed security agents grabbing a wounded Fico from the ground and hustling him into a black car. Other police handcuffed a man on the pavement nearby.

The premier’s condition has stabilised but was still “very serious” a day after the violence that prompted deep worries of an escalation in the politically polarised nation.

Authorities charged an alleged gunman with the attempted murder of the Slovak PM, saying the shooting was sparked by the election win last month of a Fico ally.

“This is a lone wolf whose actions were accelerated after the presidential elections since he was dissatisfied with its outcome,” interior minister Matus Sutaj Estok said.

Pellegrini, the Fico ally who won April’s vote, called for calm and urged political parties to halt campaigning for June’s EU parliament election. The leader of the biggest opposition party, centrist Progressive Slovakia, announced his grouping had already done so.

Slovakia’s politics have been divided for years between pro-Europeans and nationalist-leaning camps, with the latest elections heavily influenced by disinformation and verbal attacks on social media.

Pellegrini, who will assume office in June, said Slovakia should avoid “further confrontation” in a joint statement with outgoing President Zuzana Caputova.

The two politicians represent rival political camps but Caputova said they wanted “to send a signal of understanding” as she urged an end to “the vicious circle of hatred”.

Outside the hospital, shock mixed with outrage as residents of Banska Bystrica condemned the assault. “I’m certainly afraid that such attacks will be repeated,” Nina Stevulova, an 18-year-old student, said.

“There’s no need to do such things. Feel free to throw a tomato or an egg at him or scold him that ‘You are a thief or a murderer’,” Karol Reichl, a former professional driver, told AFP. “But don’t come with a gun and shoot,” the 69-year-old said.