The terrorist group Teyre Azadiye Kurdistan has claimed responsibility for a mortar attack on Sabiha Gokcen airport in Istanbul while the airport was closed for the night on 23 December.
The Turkish authorities have increased security measures at airports in Istanbul in response.
There were 2 explosions near the main Ankara train station in the Ulus area on 10 October. At least 100 people were killed and more than 180 injured.