At the Northeastern American College (Colegio Americano del Noreste) in Monterrey, Mexico, a teenage student took out a .22 caliber weapon, and fired rounds at his teacher and other students. He then turned the gun on himself.
The incident occurred yesterday, and news reports surrounding the massacre are conflicting. One teacher, two students and the shooter were shot. But it's not yet clear whether any of them died or survived.
Photos of the alleged teenager shooter have been circulating on Twitter - see above.