Turkey on Friday suspended all entries from the U.K. after reporting 15 cases of the new COVID-19 variant among arrivals from the country.

"While investigating the mutation from the U.K., the new COVID-19 variant was detected in 15 people, who entered our country from the U.K. Entries from the U.K. have now been temporarily suspended," Health Minister Fahrettin Koca said on his Twitter account.

He said they were in quarantine, along with people they had been in contact with. He said the strain was not identified in passengers from elsewhere.

Turkey suspended flights with the U.K. along with other countries in late December upon discovery of the new strain's spread and quarantined at least 4,603 passengers. Turkey also began to require a negative PCR test result for all international arrivals last week.

Meanwhile, Turkey's coronavirus death toll rose by 212 in the last 24 hours, Health Ministry data showed Friday, as a four-day curfew to curb the pandemic began. The virus has killed a total of 21,093 in the country,

The number of new COVID-19 cases stood at 12,203 over the same period, including 1,908 patients, bringing Turkey's total cases to 2,220,855 since the outbreak struck early last year.

"The number of active cases and critical patients continues to decrease. Our losses have started to fall. It will further decrease with the fall in the number of critical patients. I believe the destructive effect of the epidemic will ease," Koca added.

The current lockdown will end at 5 a.m. local time on Monday, Jan. 4.

Ankara and Istanbul, two of Turkey's largest metropolises, also have a weekday curfew in place between 9 p.m. and 5 a.m.