Slovak Prime Minister Robert Fico faces heat from the opposition after he didn’t bat an eye when a group of Slovaks living in Serbia was assaulted.

The incident took place this month in the northern city of Bački Petrovac, home to Serbia’s largest Slovak minority, where a photo exhibition documenting months of anti-government protests was vandalized. The violence later escalated into physical attacks against the organizers by supporters of Serbian President Aleksandar Vučić. The exhibition was organized as part of the Slovak National Festival.

Michal Šimečka, leader of the opposition liberal party Progressive Slovakia (PS), made a trip to Bački Petrovac and accused the Fico government of failing to protect minority rights of their fellow countrymen.

“The Slovaks in Serbia feel completely abandoned, left at the mercy of local hooligans and thugs. No one helps them, no one from our government has stood up for them, summoned the Serbian ambassador, nothing,” fumed Šimečka in a post on Facebook. He called on to Fico and the foreign minister Juraj Blanár to “act immediately.”

Fico in a press conference on Friday slammed Šimečka for interfering in Serbia’s internal political matters and accused the opposition of trying to stage similar protests in Slovakia.

“An internal matter, which is purely a sovereign issue of Serbia, has become a perfect opportunity for our opposition politicians to, on one hand, support the Serbian opposition and, at the same time, try to import this “Maidanization” we are already seeing in Serbia into Slovakia,” Fico said.

The Slovak leader also said he had no knowledge of minority rights being violated in Serbia and finished by attacking journalists at the press conference who he said hate sovereign governments like those in Serbia or Slovakia.

The anti-government protests in Serbia started last November after a railway station awning collapsed in Novi Sad, killing 16 people, and evolved into the largest protest movement in modern Serbian history.