Greek and Turkish fighter jets have collided over the Aegean Sea after shadowing each other through disputed airspace. Turkish authorities said that their own airman was rescued but the Greek pilot was killed.
Athens and Ankara have long been unable to resolve territorial disputes over the Aegean and these have frequently spilled over into the skies, with pilots engaging in mock dogfights on a daily basis.
As Nato allies, both Turkey and Greece patrol their skies with American F-16 jets and the interception manoeuvres, involving close-range fly-pasts at high speeds, have been a frequent source of protests.
Turkey claimed that the crash was the result of Greek interference in manoeuvres taking place in international airspace, but Greece claimed that the collision occurred after its own fighter was scrambled to intercept a Turkish jet over the island of Karpathos.
Turkish Foreign Minister Abdullah Gul telephoned his Greek counterpart Dora Bakoyanni, who is visiting Helsinki, after the incident.
The Greek Foreign Ministry said in a statement: "The two foreign ministers expressed their regret for today's incident and agreed that this should not affect the two countries' efforts to improve their relations."
The response was a clear signal of how far both sides have come since a dispute over the rocky outcrop of Imia in the Aegean brought Greece and Turkey close to conflict in 1996, before mutual allies negotiated a climbdown.
Since then the Aegean neighbours have launched a series of confidence building measures that have seen regular high-level visits between the traditional foes and strong support from Greece for Turkey's bid to join the European Union.
But a solution to territorial disputes over the sea shelf in the Aegean has proved elusive and Turkey refuses to recognise Greece's claim to a 10-mile zone around its coast. Ankara recognises only a six-mile zone and insists it has the right to train in international airspace.
But the issue with the greatest potential to divide them is Cyprus. The Mediterranean island was split in 1974 after Turkish forces invaded and occupied the north in response to a Greek coup in the south in 1974.
The Greek-led south of the island is now a full member of the European Union and voted in 2004 to reject a UN-brokered reunification plan that would have seen power-sharing with a Turkish-Cypriot authority in the north. The Turkish north of the island, recognised only by Ankara, voted in favour of the plan drafted by the UN secretary general Kofi Annan and has complained since of being forcibly isolated by the wealthier south.
Greek-Cypriot President Tassos Papadopoulos, who led the "no" vote against the Annan plan, was re-elected at the weekend and has warned that he might be prepared to block EU accession talks with Turkey if Ankara will not agree to a peace deal more favourable to the Greek south of the island.
The government of Recep Tayyip Erdogan in Ankara is already under pressure from secular forces, led in part by the Turkish military, on the one side and Islamists on the other.
Mr Erdogan, whose party has Islamist roots, has so far balanced those internal pressures, but the killing of a high court judge in a religiously motivated attack in Ankara last week, outlined the fault lines in Turkish politics.Reuse content