Two teenage girls were shot dead at a Glendale, Arizona, high school on Friday morning, police announced. “Both sustained a single gunshot wound,” said police officer Tracey Breeden, “and the weapon was found near them.” There is no active shooter, though the school remained on lockdown for several hours. Breeden said authorities do not know what instigated the shooting or what the 15-year-old girls’ relationships to each other were. Breeden also said the manner of the deaths has not been determined, though circumstances suggest it may have been a murder-suicide or a double suicide. The girls’ names have not been released yet. Students will be released to their parents on an individual basis, the superintendent said.