Hysteria over the novel coronavirus epidemic has sparked violent protests in Ukraine, fueled by panic and disinformation around the outbreak — even though the country has no confirmed cases of the virus.

Protests and violent clashes with police broke out in several places Thursday, as Ukraine’s authorities blamed the disorder on the spread of misinformation on social media and suggested it may have been part of a deliberate campaign targeting the country.

The trouble began as a plane carrying evacuees from China landed in Ukraine on Thursday. In a village in central Ukraine, where the evacuees were due to be taken to a health spa to be quarantined, local people began attacking police and tried to blockade the convoy carrying the evacuees.

Residents at the village of Novi Sanzhary set alight tires and barricaded the road to the spa, before attacking the convoy with the evacuees onboard. Windows on some of the buses were smashed.

Hundreds of helmeted riot officers battled with the protesters and used armored vehicles to clear tractors from the road. The fighting carried on late into the night, with 24 people arrested, police said. Nine police offices and one civilian were injured.

In other towns, people blockaded entries to local hospitals, fearing the evacuees might be diverted to them.

The disorder occurred as a wave of speculation online spread suggesting that the first cases of the virus may have arrived in Ukraine, including what appeared to be a deliberate disinformation campaign.

Namely, an email claiming to be from the Ukraine health ministry asserted that Ukraine now had 5 confirmed cases of the virus.

In reality, the email, which was sent to the ministry’s entire contact list, was fake, Ukraine’s security service, the SBU, said in a statement. The email had come from outside the country, the agency said, and the agency was investigating who was behind it.

There are no confirmed cases of the virus in Ukraine. The only two Ukrainians to be infected were aboard the Diamond Princess cruise liner in Japan and have already now recovered.

Authorities were forced to counter the misinformation. Ukraine’s Center of Public Health published a message warning that the reports of infections were fake and asked the media not to spread it.

“Attention! The reports about five confirmed cases of COVID-19 coronavirus in Ukraine are UNTRUE,” the Center for Public Health said in a statement, referring to the virus by its scientific name. “We urge the media not to disseminate this information and to inform the press service of the Health Ministry of Ukraine of the sender of this information upon receipt of the letter.”

Ukraine’s President Volodymyr Zelenskiy issued a statement urging calm and that there was no public health risk. The country’s health minister, Zoryana Skaletska, promised on Thursday to spend the two-week quarantine period with the evacuees to prove there was no danger.

The evacuees — 45 Ukrainians, 27 Argentinians and citizens from several other South American countries, as well as 22 crew members and doctors — were flown to Ukraine from China’s Hubei Province. All of them have already tested negative for the virus, authorities said, but are to be held in quarantine to ensure they aren’t carrying it.

It was unclear where the fake email originated from or how significant its role was in fueling the disorder, but on Friday, Prime Minister Oleksiy Honcharuk said he believed the disorder was the result of a deliberate campaign. In a country that is frequently the victim of Russian disinformation campaigns and major cyber attacks, that has meant some in Ukraine quickly turned their suspicions towards Moscow.

“Those events which happened yesterday, in my opinion, are the consequences also of the information war that is continuing against our country both inside and from without,” Honcharuk, who was dispatched to Novi Sanzhary to deal with the rioting, told Ukraine’s parliament on Friday. In Ukraine, “information war” most often refers to efforts by Russia to destabilize the country, alongside its military actions in eastern Ukraine.

Zelenskiy, however, on Friday appeared to lay the blame on those giving in to panic.

“Frankly speaking, we constantly say that Ukraine is Europe. Yesterday in several episodes, it seemed more like we are Europe of the Middle Ages,” Zelenskiy said.

“Let’s not forget that we are, all the same, people and not…,” he said, saying he didn’t want to use a bad word.

Ukraine’s security service in its statement said it had already established the email had been sent from a foreign provider and that the sender’s address had been altered.

Misinformation around the novel coronavirus has boomed around the world since outbreak began. In Ukraine, where trust in the health system and authorities is weak, false reports about the virus quickly spread online.

Besides the clashes in Novi Sanzhary, people also sought to block access to a hospital in the western Lviv region, burning cars and tires to create a roadblock. In Ternopil, another western city, a crowd gathered with a priest outside a health spa to pray that Ukrainians returning from China would not be brought there.

There are around 1,300 confirmed cases of the virus outside China, which has registered around 75,600 within its borders. The total death toll for the virus is 2,247. Chinese health authorities on Thursday reported a drop in the number of new infections, though there was a jump in cases in South Korea, where they rose by a hundred in a single day to reach 204.