Turkey's parliament yesterday authorised the country's military to carry out cross-border operations after clashes drew Syria's neighbour deeper into its 18-month civil war.
Nato and the UN Security Council also held emergency meetings after a Syrian mortar strike on Wednesday killed five members of a family in the Turkish town of Akcakale, provoking retaliation from Ankara. The Turkish armed forces have been shelling Syrian positions since late on Wednesday, killing several soldiers.
Turkish officials have warned that further retaliation may take place and have been moving reinforcements and ammunition supplies up to frontier bases. "This last incident is pretty much the final straw," said Bulent Arinc, Turkey's Deputy Prime Minister. "There has been an attack on our land and our citizens lost their lives, which surely has adequate response in international law."
A Syrian apology did come later in the day, following pressure from Russia. Besir Atalay, a Turkish minister, announced: "Syria accepts that it did it and apologises. They said nothing like this will happen again. That's good. The UN mediated and spoke to Syria."
Although the apology will go some way towards defusing tensions, the Turkish government stressed there will be no immediate change to its military posture. Speaking at a press conference in Akcakale yesterday, the Prime Minister, Recep Tayyip Erdogan, said he has no intention of starting a war.
"We want peace and security and nothing else. We could never be interested in something like starting a war," he said.
But he added: "The Turkish Republic is a state capable of defending its citizens and borders. Nobody should try and test our determination on this subject."
In Damascus, the Information Minister, Omran Zoabi, insisted that Syria respected the sovereignty of other states and said an investigation was underway. But he appeared to hold Turkey at least partly responsible, due to its support for the rebellion against President Bashar al-Assad.
"The Syrian-Turkish border is a long one and is being used for smuggling weapons and terrorists," said Mr Zoabi. "Neighbouring countries should act wisely and rationally and responsibly, especially in cases of the presence of armed terrorist groups who have their different agendas that are not targeting the Syrian national security but the regional security."
Akcakale was hit by four shells on Wednesday. One of the shells hit a grain mill. The others landed on a residential street just a few hundred feet from the border. Three of those who died in the blast were children who had come to the gate of their house after the first two blasts, eyewitnesses said. Two women were also killed.
Residents in Akcakale said they had been increasingly concerned that such an incident was looming. "For the last 10 days our houses have been shaking from the shelling," said Abdul Halil, 70, a farmer. Mr Halil said that many in the town were leaving. He estimated that 70 per cent of the residents had already moved away. "We do not want war, but if they attack again we want the government to attack back," he said.
There had earlier been unusual public rebuke from Russia – which has so far been a staunch supporter of Syria – with the "advice" that it needed to acknowledge that the deaths were a "tragic accident" and ensure they were not repeated. "We think it is of fundamental importance for Damascus to state that officially," said Foreign Minister, Sergei Lavrov.
After meeting to discuss the border clashes yesterday evening, the UN Security Council condemned "in the strongest terms" Syria's shelling.
"This incident highlighted the grave impact the crisis in Syria has on the security of its neighbours and on regional peace and stability," a statement said. The statement came after the council managed to bridge differences between the US and its Western allies who were demanding a strong text and Syria's most important ally, Russia, which tried to weaken the text.
Nato ambassadors also met yesterday and issued a statement saying the alliance "continues to stand by" Turkey, and demanding "the immediate cessation of such aggressive acts against an ally".
Turkey could theoretically invoke Article 5, under which an armed attack on any Nato member is considered an attack on all. However, Article 5 does not automatically result in collective military action.
The British Foreign Secretary, William Hague, said Turkey's actions were "understandable, an outrageous act has taken place, Turkish citizens have been killed inside Turkey by forces from another country". The US Secretary of State, Hillary Clinton said she too was "outraged" by the mortar attack.