Turkey announced Friday several strong new measures to stem the spread of the coronavirus, including a 15-day ban on vehicles leaving or entering 31 provinces.

President Recep Tayyip Erdogan said cities included Istanbul that is home to nearly one-fifth of Turkey’s population, as well as the urban centers of Ankara, Izmir, Bursa and Adana.

Police and gendarmerie teams began implementing measures by setting up checkpoints at entrances and exits to cities beginning at midnight.

Security forces rejected pleas of those wanting to travel, except for compulsory and necessary situations, such as commercial vehicles carrying basic or medical supplies.

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