“Young lives full of hope have been destroyed,” he said in a statement.

Local media said that the shooter, reported to be a young man who picked off his victims with unusual accuracy, began in the kindergarten section where he killed his teacher mother and her class, then moved on.

The child victims were reported to be aged between five and ten.

“I was shocked and deeply saddened to hear about today’s horrific shooting,” British Prime Minister David Cameron said.

“My thoughts are with the injured and those who have lost loved ones. It is heartbreaking to think of those who have had their children robbed from them at such a young age, when they had so much life ahead of them.”

Britain’s Queen Elizabeth II sent a message to President Barack Obama in which she said she was “deeply shocked and saddened” to hear of the shootings.

“The thoughts and prayers of everyone in the United Kingdom and throughout the Commonwealth are with the families and friends of those killed and with all those who have been affected by today’s events.”

French President Francois Hollande also extended his condolences to the victims and their relatives in a message to Obama.

“This news... horrified me and I wish to express my deep shock and consternation,” Hollande said.

The foreign ministry also issued a message in which it offered “France’s full support to the American people and authorities.”

Australian Prime Minister Julia Gillard said in a statement: “Australia grieves with America today following the mass shooting of primary school children and teachers in Connecticut.

“Like President Obama and his fellow Americans, our hearts too are broken.

“We share America’s shock at this senseless and incomprehensible act of evil.”