JERUSALEM — Seven Israeli teenagers were in custody on Monday, accused of what a police official and several witnesses described as an attempted lynching of several Palestinian youths, laying bare the undercurrent of tension in this ethnically mixed but politically divided city. A 15-year-old suspect standing outside court said, “For my part he can die, he’s an Arab.”

The police said that scores of Jewish youths were involved in the attack late Thursday in West Jerusalem’s Zion Square, leaving one 17-year-old unconscious and hospitalized. Hundreds of bystanders watched the mob beating, the police said — and no one intervened.

Two of the suspects were girls, the youngest 13, adding to the soul-searching and acknowledgment that the poisoned political environment around the Israeli-Palestinian conflict has affected the moral compass of youths growing up within it.

“If it was up to me, I’d have murdered him,” the 15-year-old suspect told reporters outside court on Monday. “He cursed my mother.” The young man who was beaten unconscious, Jamal Julani, remained in the hospital.