Turkey's military has more than 500 miles of border with Syria to defend. It has now decided to treat everything that happens on the Syrian side of the border with extreme suspicion.
The scrambling of the jets is a sign of continuing tensions. A little over a week ago, Syria shot down a Turkish warplane. Syria says that the aircraft was flying inside Syrian airspace - a charge denied by Turkey.
Following this incident, the Turkish government announced that it had revised its military rules of engagement towards Syria. From now on, every military element that approached the Turkish border from Syria would be considered as a threat. The military has now acted on its new rules.
Turkey is keen to show that it's protecting its territory. The government allows its southern border region of Hatay to be used as a staging ground for Syrian opposition rebels. But it doesn't want this region to become an actual battleground...
