OSAKA — Six teenage boys are in custody on suspicion of attempted murder in connection with a June 6 attack in which three minors were injured in Kadoma, Osaka Prefecture, police sources said.

The six being held as of Sunday, aged between 16 and 18, conspired to attack other groups and assaulted eight male motorcyclists with baseball bats when they were passing by them on a national route in Kadoma early on June 6, police alleged.

Three of the victims, aged between 14 and 16, including a third-year junior high school student, sustained injuries and one of them suffered a fractured skull, police said.

Authorities said the six suspects, including three high school students, graduated from the same junior high school and were frequently in trouble in and around Kadoma. They owned up to most of the charges, police said.