Turkey is pressing its military offensive against US-allied Kurdish fighters in northeast Syria, shelling towns and bombing targets from the air in an operation that has forced thousands of people to flee their homes.
At least 23 fighters with the Kurdish-led Syrian Democratic Forces (SDF) and eight civilians, two them SDF administrators, have been killed, the Syrian Observatory for Human Rights said.
Three people including a child were killed in mortar fire in the border town of Akcakale, hospital and security sources said.
The SDF has not given a casualty toll, while six fighters with Turkey-backed rebel groups have also been killed.
More than 60,000 people have fled since the offensive began, the Observatory added.
The towns of Ras al-Ain and Darbasiya, some 60km to the east, have been largely deserted as a result of the attack.
Turkish President Tayyip Erdogan told members of his AK Party in Ankara that 109 militants had been killed so far in the two days of fighting.
Kurds said they were resisting the assault.
According to a senior Turkish security official, armed forces struck weapons and ammunition depots, gun and sniper positions, tunnels and military bases.
Jets conducted operations up to 3km into Syria, and a Reuters witness saw shells exploding just outside the town of Tel Abyad.
"The operation is currently continuing with the involvement of all our units ... 109 terrorists have been killed so far," Erdogan said in a speech to members of his AK Party in Ankara on Thursday.
NATO member Turkey has said it intends to create a "safe zone" for the return of millions of refugees to Syria.
But world powers fear the operation could intensify Syria's eight-year-old conflict, and runs the risk of Islamic State prisoners escaping from camps amid the chaos.
Erdogan sought to assuage those concerns, saying that militants from the jihadist group would not be allowed to rebuild a presence in the region.
Taking aim at the EU and Arab powers Saudi Arabia and Egypt, which have voiced opposition to the operation, Erdogan said those objecting to Turkey's actions were dishonest.
He threatened to permit Syrian refugees in Turkey to move to Europe if EU countries described his forces' move as an occupation.
Turkey is hosting around 3.6 million people who have fled the conflict in Syria.
"They are not honest, they just make up words," Erdogan said in a combative speech, singling out Saudi Arabia and Egypt.
"We, however, take action and that is the difference between us."
The Turkish operation began days after a pullback by US forces from the border, and senior members of President Donald Trump's own Republican Party condemned him for making way for the incursion.
The decision has been widely criticised as an abandonment of Syrian Kurds.
Ankara brands the Syrian Kurdish YPG militia as terrorists because of their ties to militants who have waged an insurgency in Turkey.
But many members of Congress, and US officials, credit the Kurds with fighting alongside American troops to defeat Islamic State militants.