President Barack Obama has offered his sympathy and gratitude to the principal of a Pennsylvania school where a teenager stabbed 22 people.
The White House says Obama called Principal Ron Suvak of Franklin Regional High School on Thursday as the president flew home from a two-day trip to Texas.
White House spokesman Jay Carney says Obama offered his deepest sympathies to those affected. He says Obama talked about the heroism of students, teachers and staff whose actions saved lives.
Obama also thanked first responders who treated victims and told the principal that the federal government will offer whatever law enforcement help is necessary.
Officials say a 16-year-old boy slashed away at students and a school security guard Wednesday in Murrysville.