Slovak prime minister Robert Fico was in a "stable" but "serious" condition, his deputy said Wednesday, a week after he was shot four times in an assassination attempt that shook the deeply polarised country.

The Slovak premier was shot as he was greeting supporters after a government meeting in the central town of Handlova.

He underwent a five-hour operation immediately after the attack and another on Friday at a hospital in the central city of Banska Bystrica, where he still remained on Wednesday.

"His condition was stable in the morning," deputy prime minister Robert Kalinak told reporters after the Slovak Security Council's extraordinary meeting on Wednesday.

"His condition is serious, the injuries are complicated. Transportation is definitely out of the question at this time," said Kalinak, Fico's closest political ally in the eastern European country.

He added the hospital in Banska Bystrica would issue a new update on Fico's health later on Wednesday.

The suspected gunman, identified by Slovak media as 71-year-old poet Juraj Cintula, has been charged with premeditated attempted murder and was remanded in custody following a hearing on Saturday.

- Deleted account -

On Sunday, the Slovak interior minister said that police were looking into the possibility that Cintula may not have acted alone.

"One version is that the culprit was part of a group of people who encouraged each other to commit the crime," Matus Sutaj Estok said, adding the gunman may have disclosed his intentions to someone.

Citing intelligence reports, Sutaj Estok said that someone had erased the gunman's history and communication on Facebook while he was detained.

But the Slovak media regulatory agency said Facebook-owner Meta informed the authorities it had deleted the suspect's account.

"Meta informed us that in accordance with the crisis protocol they put in place following the attack, they deleted the attacker's Facebook account," the Council for Media Services said in a statement on Tuesday.

According to Slovak daily Dennik N, Meta deleted the profile on the day of the attack.

But Kalinak, who is also Slovakia's defence minister, said Wednesday a "distinction" has to be made between the Slovak investigation findings and Meta's report.

"We talked about the manipulation of the account shortly after the arrest, that's the time between the attack and the intervention of the Meta company," he said.

The attempted assassination has highlighted acute political divisions in Slovakia where 59-year-old Fico took office in October after his centrist populist Smer party won a general election.

He is serving his fourth term as prime minister after campaigning on proposals for peace between Russia and Slovakia's neighbour Ukraine, and to halt military aid to Kyiv, which his government has done.