DIYARBAKIR/ANKARA (Reuters) - Six children were among eight civilians wounded when three rockets fired from Islamic State-controlled territory in Syria hit a Turkish border town on Thursday, the Turkish military said.

The attacks on Kilis were the first since Turkish-backed Syrian rebels swept into northern Syria last month to clear Sunni Islamist fighters from Turkey’s southern border. That operation, dubbed “Euphrates Shield” by Turkey, was launched after months of attacks on Kilis reduced parts of the town to rubble.

U.S.-led coalition forces carried out 20 air strikes against Islamic State targets in northern Syria on Thursday, “neutralizing” 40 militants, the Turkish military said.

“As of 1800 hours (1500 GMT) clashes were continuing between (Syrian) rebels...and Daesh terror group elements who carried out a broad attack to take back areas they had lost,” it said in a statement, using an Arabic acronym for Islamic State.

It said the Turkish Air Force also carried out strikes on Islamic State targets, destroying five buildings, while six rebels were wounded in an Islamic State car bomb attack northeast of the town of Azaz.

“We entered Syria because these rockets are damaging property and human life. We want to establish security,” Prime Minister Binali Yildirim told reporters in Ankara.

The military said it tracked the origin of the rockets fired at Kilis using radar, and returned fire.

At least six of the injured were Syrian nationals, Mayor Hasan Kara said. Kilis is home to many refugees from the Syrian civil war.

Cross-border rocket attacks have killed 21 people and wounded 80 in Kilis since January, security sources said.

Rockets attacks on Kilis have provoked local outrage against the Turkish government, which some residents say is failing to protect them. In April police used tear gas to disperse dozens of people protesting after a rocket attack killed one person and wounded 26.

EUPHRATES SHIELD

Turkish tanks rolled into Syria from Kilis province this month as part of “Euphrates Shield”, which has helped the Turkish-backed rebels sweep Islamic State from a 90-km (55-mile) stretch of Turkey’s border.

The campaign, launched in August, is also intended to stop the advance of fighters of the Syrian Kurdish YPG, which Turkey sees as an extension of the outlawed Kurdish militant PKK it is fighting in its own largely Kurdish southeast.

While the Turkish-backed rebels have made swift gains in Syria, the wedge of land they control is shallow, and beyond it lies Islamic State territory.

President Tayyip Erdogan said this week the rebel alliance of Syrian Arabs and Turkmen fighting under the banner of the Free Syrian Army could extend their zone of control in northern Syria by pushing south and attacking the Islamic State-held town of al-Bab.

Turkey’s “safe zone” in the region could eventually span an area of 5,000 square km (1,900 square miles), from around 900 square km now, he said.

Turkey has long argued for a “safe zone” or “no-fly” zone along its Syrian border, with the aim of clearing out Islamic State and Kurdish fighters and stemming a wave of migration.

Western allies have so far balked at the idea, saying it would require a significant ground force and planes to patrol.