LUCKNOW, India (AP) — Police in northern India say they have detained 15 suspects after a woman and her teenage daughter were gang-raped off a busy highway.

Police say the attack took place Friday night near the town of Bulandshahr in Uttar Pradesh state after the car the women were traveling in was attacked by a gang of men with an iron rod.

Senior local police official Daljeet Choudhary said Sunday that several police teams were at work to ensure that the attackers were identified quickly.

The woman, her daughter and three male relatives were also robbed of money, jewelry and their cellphones.

The attack is the latest incident of sexual violence to shock India, a still-deeply patriarchal nation of 1.3 billion people.