The shooting rampage at a U.S. elementary school Friday in Newtown, Connecticut that left 28 people dead, including 20 young children, has prompted reactions of shock and sympathy from around the world.

Australian Prime Minister Julia Gillard described the attack as an “incomprehensible act of evil.” She said that like U.S. President Barack Obama and his fellow Americans, “our hearts too are broken.”

British Prime Minister David Cameron said he was “shocked and deeply saddened” to learn of what he called a “horrific shooting.”

French President Francois Hollande said he was “horrified” by the news of the shooting.

The European Union diplomacy chief, Catherine Ashton, expressed her shock at the incident, and the head of the European Commission, Jose Manuel Barroso, spoke of his “deep shock and horror” at the shooting.

Britain's Queen Elizabeth sent a message to President Obama, saying she was “deeply shocked and saddened” by the deadly incident.

Witnesses say the 20-year-old gunman entered the school at mid-morning and opened fire on children and their teachers in two rooms. A military assault rifle was later found in the gunman's car. The shooter, identified as Adam Lanza, died at the scene of a self-inflicted gunshot. Two semi-automatic handguns were found nearby.

Authorities say the shooter killed his mother at her home before driving her car to the school.

Police have not established a motive for the killings.