Zagreb, Croatia (CNN) -- At least seven people were killed and dozens were injured after a powerful 6.4 magnitude earthquake struck central Croatia on Tuesday, according to the US Geological Survey and Croatian officials.
Emergency crews, assisted by the military, were still digging through the rubble in several towns as night fell and electricity remained out.
The quake, which struck just after noon local time about 30 miles southeast of the capital Zagreb, could be felt across the Balkans. It is the largest quake to hit Croatia this year, according to the European-Mediterranean Seismological Centre.
Prime Minister Andrej Plenkovic said the death toll was expected to rise. And he appealed to private citizens not to go to the worst-hit town, Petrinja, which was near the epicenter.
"At this moment, we don't know exactly how many people have died. The latest information before the core cabinet meeting was seven people," Plenkovic said. "We have some indication that this number may be higher, so we'll wait and see for the police's official report."
A girl in the town of Petrinja, a man found inside a collapsed church in the village of Žažina, and five men in the village of Majske Poljane, were among the dead, according to Croatia's Interior Ministry and local media reports.
"We are doing everything we can to help the citizens of Petrinja and surrounding areas in this dramatic and tragic situation," Interior Minister Davor Bozinovic said in a tweet.
"The destructive earthquake has taken human lives, destroyed homes, and we deeply sympathise with every person and every family that has been harmed."
Croatian town 'going through hell'
Petrinja Mayor Darinko Dumbovic told CNN affiliate N1 that the town of nearly 25,000 residents was "going through hell" after the tremor, and had no running water or electricity. He has requested emergency aid.
"I feel that both its center and its soul have been destroyed," Dumbovic said. "We have no electricity, no water. Everything is broken. We are here in darkness, in ruin, searching for people," he added.
HEP, the state electricity provider, said it had managed to restore power to parts of the quake-hit area; however Petrinja and its hospital remain dark, N1 reported. HEP said it was hoping to restore some power during the evening.
Footage from inside the hospital showed medical staff working by torchlight as they awaited the evacuation of some patients.
All the patients in Petrinja hospital have now been evacuated, as well as 80% of those who were in Sisak hospital, the Prime Minister said Tuesday evening. The patients were evacuated by the military -- mostly to Zagreb.
More than 250 members of the Croatian armed forces are on the ground, according to a statement from Defense Minister Mario Banozic, shared by the Croatian government's official Twitter account.
"The military barrack in Petrinja is open and can provide adequate accommodation for those who have lost a roof over their heads. The army shall be here for however long it is needed," the tweet said.
In dramatic footage captured by N1, the mayor was giving a press conference on camera about the previous day's smaller earthquake when Tuesday's quake struck. In the video, a rumbling sound can be heard as the earthquake begins, followed by muddled shrieks from the attendees. The camera then appears to fall to the ground.
In an earlier interview with N1, Dumbović described scenes of "panic" in the aftermath of the tremor.
"We are pulling people out of cars, we don't know if people have died or have been injured. I heard a kindergarten has collapsed but luckily there weren't any children there, while in another one the children were able to escape," the mayor said.
Prime Minister visits
Plenkovic visited the towns close to the epicenter of the earthquake, as search and rescue missions continued.
"I'd like to express my condolences to the families of the victims of the earthquake in Petrinja and Glina. We hope that the number of victims will be as low as possible," Plenkovic said in a tweet.
"All emergency services are in action on the field and are working tirelessly to provide help to all those who need it," he added.
The Arena sports hall in Zagreb, which was turned into an emergency care center for coronavirus patients, will also begin to take in coronavirus patients from the county of Sisak-Moslavina, which was affected the earthquake, HINA reported.
Krsko nuclear power plant in Slovenia, close to Zagreb, has been closed as a precaution, N1 reported.
The Prime Minister said the government has secured 120 million kuna ($19 million) from the state budget to help with the response. Croatia has also activated the EU Civil Protection Mechanism, which helps provide disaster relief.