More than two dozen people, including 18 children, died Friday in a shooting at an elementary school in Newtown, Connecticut, authorities told U.S. media outlets.
The fatalities also include one suspect and the principal of Sandy Hook Elementary School.
Police said they were searching for a second suspect.
ABC News cited sources who described one of the shooters as a man of 24 equipped with four weapons and wearing a bullet-proof vest.
Authorities were first alerted by a 911 call at 9:41 a.m. and Connecticut state police quickly dispatched emergency units to the school in Newtown.
Sandy Hook Elementary has 450 students.
Newtown officials put all public and private schools in the area on lockdown.
Police escorted the surviving students out of Sandy Hook, telling them to hold each other's hands and keep their eyes closed until they were outside, a 9-year-old girl told the Hartford Courant.
President Barack Obama is being kept informed on developments in Newtown, White House press secretary Jay Carney said. EFE