More than 1,600 Syrians have fled to Turkey in the last two days, Turkish authorities said on Thursday, to escape what activists said was Syrian army shelling of villages near the northern Syrian towns of Idlib and Aleppo.
The numbers fleeing were the highest since March 15 when around 1,000 Syrians entered Turkey in one day.
Since then, around 300 to 400 Syrians have fled each day. Turkish leaders have said a flood of refugees or massacres of civilians by Syrian troops near its border could force them to act to prevent a humanitarian disaster.
Turkish Prime Minister Tayyip Erdogan said last month that setting up a "safe" or "buffer" zone along the border was among the options his government was considering. But that would mean sending in troops to secure the area, which could lead to confrontation between Syrian forces and the Turkish army, the second biggest in NATO.
Turkey's disaster and emergency management authority said 1,622 Syrians had fled to Turkey in the last two days, bringing the total number there to 21,285, of which 65 were in hospital.
Turkey-based Syrian opposition activists Omar al-Kilani and Muthana Barakat attributed the influx to the Syrian military bombarding some 10 villages around Idlib and Aleppo in the run-up to April 10, the date set by peace envoy Kofi Annan for a Syrian troop withdrawal from restive cities.
Both activists cited information from refugees arriving from the area of the fighting.