Turkey shelled Syria in retaliation for deadly cross-border fire today as NATO convened an emergency meeting on the attack that threatened to inflame tensions in the volatile region.

Earlier today Syrian shells crashed into a Turkish border town, killing five people, the first time Turkey’s citizens were killed by cross-border fire from its war-torn neighbour.

An outraged Ankara said the attack went “too far”, and it swiftly retaliated.

“Our armed forces in the border region immediately retaliated against this heinous attack... by shelling targets spotted by radar,” Turkey’s Prime Minister’s Office said in a statement.

“Turkey will never leave unanswered such provocations by the Syrian regime targeting our national security, in line with engagement rules and international law.”

The Syrian shelling was condemned by the US, which said it was “outraged” by the attack, while UN chief Ban Ki-moon told Damascus to respect its neighbours’ sovereignty.

The North Atlantic Treaty Organisation, of which Turkey is a member, expressed “its strong condemnation” of the Syrian shelling, said a spokeswoman.

“It has been decided that the NATO council will meet urgently,” Turkey’s Prime Minister’s office said.

Diplomatic sources in Brussels said the alliance would meet this evening.

Relations between Syria and Turkey have steadily deteriorated since the start of the uprising against Syrian President Bashar al-Assad’s regime first broke out in March 2011.

The Syrian shells crashed into the Turkish border town of Akcakale, which has been hit by Syrian fire several times recently and where schools have been shut over the past two weeks because of the violence.

The shells killed five Turkish nationals, including a mother and her three children.

Protests to UN, NATO

Earlier, Turkey protested angrily to the UN and NATO after Syrian shelling today killed five people in a town near the border.

Turkish Foreign Minister Ahmet Davutoglu called UN chief Ban Ki-moon, NATO chief Anders Fogh Rasmussen and the UN’s Syria peace envoy Lakhdar Brahimi over the incident, his office said.

Davutoglu expressed Turkey’s “deepest concern” to Ban, the UN chief’s spokesman said.

Ban encouraged Davutoglu to “keep open all channels of communication with the Syrian authorities with a view to lessening any tension that could build up as a result of the incident,” spokesman Martin Nesirky said.

Ankara also stressed that an attack on any NATO member is an attack against the entire alliance.

“The last incident went too far,” Deputy Prime Minister Bulent Arinc was quoted as saying by Anatolia news agency.

“NATO treaty articles bring about certain liabilities when one of its members is attacked.

“We will not be blinded by rage, but we will protect our rights to the end in the face of an attack on our soil killing our people,” he warned.

The shells fired from Tall al-Abyad just across the border in Syria smashed into buildings in Akcakale, the second time that fire from Syria killed people inside Turkey since the uprising against the regime in Damascus erupted in March 2011.

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