Turkish police have detained 15 people over a suicide bombing in the northwestern city of Bursa where a woman injured eight bystanders as she blew herself up near the city's main mosque, Turkish media said on Thursday.
The TRT and CNN Turk television stations quoted Interior Minister Efkan Ala as giving the total and saying evidence pointed to a link with a militant group, but gave no details.
The attack on Wednesday was the fifth suicide bombing in a major urban center in Turkey this year.
"Fifteen people have been detained in connection with the Bursa attack. There are strong indications that it is related to a group," the broadcasters quoted Ala as saying.
Some of those detained were brought in from outside of Bursa and were being questioned at the provincial police headquarters, CNN Turk said.
No group has claimed responsibility. Two attacks this year in Istanbul, Turkey's largest city, have been blamed on the radical Islamic State movement. Two in the capital Ankara were claimed by a Kurdish militant group.
Turkey has also faced attacks from far-left groups, mostly targeting police and security forces. The Bursa attack came a day after the United States warned American citizens in Turkey about credible terrorist threats to tourist areas.
Bursa is Turkey's fourth-largest city, an industrial hub directly south of Istanbul across the Marmara Sea. While not one of the country's biggest tourist destinations, it draws some foreign visitors with its Ottoman-era architecture.