ISTANBUL — A car bomb exploded in the Turkish capital, Ankara, on Wednesday, striking a convoy of buses carrying Turkish soldiers and killing at least 28 people, government officials said.
The convoy was attacked when the buses had stopped for a red light, officials said. Deputy Prime Minister Numan Kurtulmus said 61 people were injured.
The large explosion took place close to the parliament headquarters, government buildings and a residential military facility in the central Kizilay district, according to local media reports.
Omer Celik, a spokesman for the ruling Justice and Development Party, said on Twitter that the explosion was an act of terrorism, although he did not provide details. No group immediately claimed responsibility.
Images broadcast on television showed a large fire and smoke in the area. As many as 20 ambulances have been dispatched to the scene, according to CNN Turk, a private broadcaster.
The explosion Wednesday comes four months after the capital was rocked by the deadliest terrorist attack in the country's modern history, when two suicide bombers — believed by the government to have links to the Islamic State — struck a peace rally in Ankara, killing more than 100 people.
In recent months, Turkey has stepped up its cooperation with the U.S.-led coalition fighting the Islamic State in Syria, and has been attacked several times. Last month, a suicide bomber killed at least 10 tourists in Istanbul's popular Sultanahmet district.
In a separate conflict, the Turkish military has been carrying out a large-scale counterinsurgency campaign against Kurdish militants in the country's volatile southeast, after the breakdown of a fragile peace process in July.
Since December, many towns have been under round-the-clock curfews as Turkish military forces have clashed with Kurdish militants from the Kurdistan Workers' Party, known as the PKK, who have been fighting for autonomy and more rights for three decades. The PKK has previously carried out several attacks on military targets in Turkey, but usually in the southeast.
The Turkish army on Wednesday also shelled positions held by Kurdish militias in northern Syria that it deems to be an extension of the PKK for a fourth day in a row. The government fears that the Syrian Kurds' expansion across Turkey's 560-mile border with Syria will fuel separatist ambitions among Turkey's own Kurds.