Twenty-eight people were killed and dozens wounded in Turkey's capital Ankara on Wednesday when a car laden with explosives detonated next to military buses near the armed forces' headquarters, parliament and other government buildings.
The Turkish military condemned what it described as a "contemptible and dastardly" attack on the buses as they waited at traffic lights in the administrative heart of the city.
Deputy Prime Minister Numan Kurtulmus said 28 people including soldiers and civilians had been killed and 61 wounded in the blast, which took place near a busy intersection less than 500 metres from parliament during the evening rush hour.
Justice Minister Bekir Bozdag described the attack as an act of terrorism and told parliament, which was in session when the blast occurred, that the car had exploded on a part of the street lined on both sides by military vehicles.
In a statement, French President François Hollande called the bombing an “odious attack” and expressed “support and solidarity with the Turkish authorities and the Turkish people”.
A senior security source said initial signs indicated that Kurdish militants from the outlawed Kurdistan Workers Party (PKK) were responsible. Separate security sources in the southeast, however, said they believed Islamic State (IS) group militants may have been behind the bombing.
There was no immediate claim of responsibility.
Turkish Prime Minister Ahmet Davutoglu immediately scrapped his trip to Brussels for a mini-summit on Europe's refugee crisis, diplomats said Wednesday. The talks, taking place ahead of a full summit of the 28-nation European Union, were to gather the leaders of 11 EU countries and the Turkish PM to focus on how to resettle Syrian refugees who have fled to Turkey.
“I heard a huge explosion. There was smoke and a really strong smell even though we were blocks away,” a Reuters witness said. “We could immediately hear ambulance and police car sirens rushing to the scene.”
Images on social media showed the charred wreckage of at least two buses and a car. The explosion sent a large plume of smoke above central Ankara.
Turkey, a NATO member, faces multiple security threats. It is part of a US-led coalition fighting the IS group in neighbouring Syria and Iraq, and has been shelling Kurdish militia fighters in northern Syria in recent days.
It has also been battling militants in its own southeast from the PKK, who have fought a three-decade insurgency for Kurdish autonomy. The group has frequently attacked military targets in the past, although it has largely focused on the mainly Kurdish southeast.
Wednesday’s bombing comes after an attack in Ankara in October that was blamed on the IS group when two suicide bombers struck a rally of pro-Kurdish and labour activists outside the capital’s main train station, killing more than 100 people.
A suicide bombing in the historic heart of Istanbul in January, also blamed on the IS group, killed 10 German tourists.
Meanwhile in Sweden on Wednesday an explosion severely damaged part of a building that housed a Turkish cultural association.
Police said all the windows of the centre, in a Stockholm suburb, were blown out and that technicians were on site to investigate the cause. “No one was inside. No one was injured. It had been locked since earlier in the evening,” a police spokesman said. No one has been arrested and there are currently no suspects, he added.