People across the US have observed a moment of silence one week after gunman Adam Lanza killed 20 children and six adults at Sandy Hook Elementary School in Connecticut.

Bells in Newtown tolled 26 times – for each victim of the attack at Sandy Hook Elementary School.

Adam Lanza, 20, carried out the attack at 09:30 EST after killing his mother. He later shot himself dead.

The moment of silence comes as the main US gun lobby group, the NRA, is set for a news conference on the shootings.

Funerals for those killed have taken place throughout the week, and continue in Newtown on Friday.

Connecticut Governor Dannel Malloy has asked people throughout the state to join the moment of silence, and churches in many other states have said they will join in ringing their bells 26 times.

The governor, with his deputies, marked the moment on the steps of Edmond Town Hall in Newtown.

Governor Dannel Malloy has called Friday a “day of mourning” and invited the governor of other states to participate in the acts of remembrance.

President Barack Obama said he would observe the tribute to the shooting victims privately.

Since the mass shooting, the Obama administration has indicated that it will look for ways to tighten gun laws in the wake of the attack.

People across the US have observed a moment of silence one week after gunman Adam Lanza killed 20 children and six adults at Sandy Hook Elementary School in Connecticut.

Vice-President Joe Biden has been assigned to lead the response to the Sandy Hook massacre, and Barack Obama has demanded a set of “concrete proposals” within a month.

Speaker of the House John Boehner has said the Republican-controlled chamber would consider new proposals.

In Washington on Friday, influential National Rifle Association (NRA) is due to hold a news conference on Friday morning after remaining largely silent in the aftermath of the shooting.

Representatives of the group will speak at 10:45 EST.

On Tuesday, the group issued a statement saying: “Out of respect for the families, and as a matter of common decency, we have given time for mourning, prayer and a full investigation of the facts before commenting.”

But the group said it would offer “meaningful contributions” to make sure such tragedies do not happen again.

The guns used in the shooting had been legally bought by the gunman’s mother, Nancy Lanza.

The incident has seen some pro-gun congressmen say the mass shooting has prompted them to change their views on whether guns should be regulated more strictly in the US.

Meanwhile California Senator Dianne Feinstein, who has been an advocate for tighter gun laws, said she would introduce new legislation when Congress meets for the first time in the new year.

But there is no bipartisan consensus on the issue, with some arguing that teachers in schools should be armed in order to better defend students if a shooting occurs.

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