The number of coronavirus cases in Turkey has risen to 18, Presidential Communications Director Fahrettin Altun said late Sunday.

"Our government continues to take strong measures to confront the coronavirus. The number of cases in Turkey has unfortunately risen to 18 today," he said.

"We are implementing strong monitoring protocols in our land and sea borders in addition to already strict measures at our airports," Altun said.

Of the 18 cases, seven were people who returned from European countries and three came from the U.S., Health Minister Fahrettin Koca said earlier Sunday.

"The situation is saddening, but self-isolation is the safe way for all of us," Koca stated in his tweet.

Turkey has closed its borders and halted most international flights as the coronavirus pandemic sweeps the globe. Authorities repeatedly warn the public to not travel abroad and if they do so, to impose self-isolation for 14 days. No deaths have been reported in Turkey, and the government is assuring the public that measures are in place while recommending precautions for all.

It remains a challenge to impose quarantines for everyone returning from abroad but the government managed to arrange a quarantine for a large group that returned from Saudi Arabia after performing the Umrah, or lesser pilgrimage in Islam. Thousands are being accommodated at student dormitories in the capital Ankara and central city of Konya for quarantine. Dormitories were already emptied as Turkey announced a mandatory break for universities and grade schools. The country also moved up the final day for return flights from Europe for Turkish nationals from March 17 to Sunday.