A car bomb in Istanbul killed 11 people and wounded 36 others during morning rush hour Tuesday.
A police bus was the target. Seven police officers were killed.
The blast happened on the second day of the Muslim holy month of Ramadan. It is the latest of several attacks in Istanbul and Ankara this year.
Istanbul Governor Vasip Sahin spoke at the scene of the blast, or explosion. He said a bomb inside a car blew up as a police vehicle passed by, according to the Associated Press.
Many ambulances were sent to the scene. The bomb went off in a central historic district, near Istanbul University and Bayezit Square -- a popular tourist destination.
There was no immediate claim of responsibility for the bombing.
Turkey has been struggling against Kurdish groups. The state-run Anadolu Agency reported that police held four suspects.
Turkish President Recep Tayyip Erdogan said Turkey's fight against terrorists will continue to the end. He made the comments after visiting the wounded being treated in a hospital.
The Associated Press reported that authorities have a “news blackout” — meaning the media cannot report details of the investigation. There are concerns about security and police efforts to investigate the attack.
The police bus was turned over by the force of the blast. It also damaged nearby buildings, including a closed hotel. Its entrance appeared ruined, and windows were blown out.
The blast also broke the stained glass windows of a 16th-century Ottoman mosque.
U.S. Ambassador to Ankara John Bass said in a Twitter message that "such senseless violence could never be rationalized by any cause." The United States will "continue to stand shoulder-to-shoulder with Turkey in the fight against terrorism," Bass said.
Many world leaders expressed their alliance with Turkey and their rejection of terrorism.
Kurdish rebels fighting for autonomy — or independence -- have attacked police and military targets in the past.
Last month, at least eight people, including soldiers, were wounded by a car bomb. The target was a military vehicle in Istanbul. The Kurdish worker's party, or PKK, claimed responsibility for that bombing.
Two blasts in Ankara took dozens of lives earlier this year. The Kurdistan Freedom Falcons, or TAK, a radical group that broke off from PKK, claimed responsibility.
Words in This Story
rush hour - n. a time during the day when many people are traveling on roads to get to work or to get home from work
blast - n. explosion; a loud sound
scene - n. an area where the action takes place
district - n. an area established by a government for official government business