Church bells tolled 26 times in Newtown, Connecticut Saturday for the 20 schoolchildren and six adults massacred exactly a year earlier, as U.S. President Barack Obama urged tougher gun controls.

On December 14, 2012, a heavily armed man entered an elementary school in Newtown, Connecticut and, within 10 minutes, killed 26 people before taking his own life.

U.S. authorities on Wednesday released audio recordings of emergency calls made to police from the elementary school in Newtown where a lone gunman shot dead 20 children and six adults last year.

Recordings of a series of 911 calls made from within and nearby the school were released nearly a year after the tragedy at Sandy Hook Elementary School on December 14, 2012.

The Newtown schools superintendent says they are preparing for a "normal" day, but it will likely be anything but that when classes resume for Sandy Hook Elementary School students for the first time since a gunman killed 20 of their classmates.

With their original school still being treated as a crime scene, the students will begin attending classes at a refurbished school in the neighboring town of Monroe on Thursday. Law enforcement officers have been guarding the new school, and by the reckoning of police, it is "the safest school in America."

Students at the elementary school where a gunman massacred 26 children and teachers last month were returning to class for the first time Thursday in a new building adapted to look exactly like their old one.

Sandy Hook Elementary School in Newtown, Connecticut has been closed since the December 14 tragedy in which a 20-year-old local man shot 20 small children and six staff members before committing suicide.

The father of the deranged gunman who massacred 20 small children and six other people at an elementary school and also killed his mother has finally been able to lay his son's body to rest.

A family spokesman told AFP that Peter Lanza, a tax executive at General Electric, "claimed Adam Lanza's body on Thursday and there were private arrangements that took place over the weekend."

Newtown marked Christmas amid snow-covered teddy bears, stockings, flowers and candles left in memorial to the 20 children and six adults shot dead in the second-largest school shooting in U.S. history.

The outpouring of support for the Connecticut community continued through Christmas Eve, with visitors arriving with cards, handmade snowflakes and sympathy.

U.S. President Barack Obama vowed Sunday to use all his power to stop gun massacres like the slaughter of 20 little children at a Connecticut school, saying "these tragedies must end."

Obama vented passion and anger as he told the grief-stricken community of Newtown, reeling from the unspeakable horror of Friday's rampage, that he was consoling victims of the fourth mass shooting of his presidency.

A heavily armed young gunman slaughtered 20 small children and six adults at a school in an idyllic Connecticut town on Friday, in one of the worst mass shootings in U.S. history.

Connecticut State Police spokesman Lieutenant Paul Vance said 18 children were shot dead inside Sandy Hook Elementary School and that two more died of their wounds in hospital.