According to local media reports, nearly 100 members of the self-proclaimed People's Republic of Donetsk entered the airport on Thursday, demanding the right to check the arrivals.

Elsewhere, protesters in the eastern Ukrainian city of Slavyansk have seized the local TV station, taking all Ukrainian channels off the air.
Meanwhile, the Ukrainian government has imposed entry bans on Russian citizens who want to enter the country.

In a statement, Russian airline Aeroflot warned passengers that the Ukrainian authorities were "massively restricting" entry to the country.

"In line with an official order received by the company, all Russian male citizens aged from 16-60 will be refused entry into Ukraine," the statement said.

According to Aeroflot, exceptions would only be made in extreme cases.

The measures come two days after acting President Oleksandr Turchynov announced an "anti-terrorist operation" in eastern Ukraine against pro-Russian protesters.

Tensions remain high in the region as protesters continue to occupy government, police and other administrative buildings in nearly 10 cities close to the Russian border. They have been demanding local referendums on independence.

Protests gained momentum in the eastern and southern parts of Ukraine after Crimea declared independence from the former Soviet state and formally applied to become part of the Russian Federation following a referendum on March 16.

In the referendum, almost 97 percent of the participants voted for joining Russia, with a turnout of more than 83 percent.

SHI/SHI