The shooting occurred on 15 May as the prime minister was greeting supporters after a government meeting in Handlova, a town in central Slovakia.

Fico underwent a five-hour operation immediately afterwards and a shorter one on Friday in a hospital in the city of Banska Bystrica, where he remains.

"His condition was stable during the morning," Deputy Prime Minister Robert Kalinak told reporters after a meeting of Slovakia's Security Council on Saturday.

"His condition is serious and his injuries are complicated. Transport to a [Bratislava] hospital is definitely out of the question for now," said Kalinak, Fico's closest political ally.

Late on Saturday afternoon, the Banska Bystrica hospital issued a statement on Fico's condition.

"The patient's condition is serious, but currently stable," the hospital said on social media.

"The medical board confirmed that the treatment and medical interventions chosen for the prime minister to date were appropriate," it added.

The alleged attacker, named by Slovak media as 71-year-old Juraj Cintula, was remanded in custody by a court on Saturday on suspicion of attempted premeditated murder.

On Sunday, Slovak Interior Minister Matus Sutaj Estok said police were investigating whether the gunman had acted alone.

Citing intelligence reports, Estok said someone had deleted the gunman's Facebook history and communications while he was in custody.

But Slovakia's media regulator said that Meta, which owns Facebook, had informed the authorities that it had deleted the suspect's account.

Also on Sunday, Kalinak, who is also Slovakia's defence minister, said it was necessary to "distinguish" between the Slovak investigation's findings and Meta's report.

"We talked about the manipulation of the account shortly after the detention, that is, between the attack and the intervention of the Meta company," he said.

The assassination attempt has highlighted deep political divisions in the country, where Fico, 59, took office in October after his populist-left Smer party won a parliamentary election.

Fico is serving his fourth term as prime minister, having campaigned on a promise to end military aid to Ukraine, which his government has since implemented.

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