The Turkish military has struck at targets inside Syria in reponse to a mortar bomb fired from inside Syrian territory.
The attack reportedly killed five Turkish civilians including children in the border town of Akcakale.
The prime minister’s office said Turkish armed forces responded immediately to what it called an “abominable attack”, blaming the Syrian regime for provoking Turkey’s national security.
The shell fell in the middle of a residential area and injured at least nine other people.
The attack has prompted NATO’s ambassadors to meet – an event that occurs when a member state feels its territorial integrity is under threat.
The Turkish parliament is to hold an emergency session on Thursday morning to discuss a possible military operation in Syria.