Some American politicians have criticised comments by the National Rifle Association about the need to provide armed guards in schools.
The influential National Rifle Association (NRA) which opposes tighter controls on weapons, has held its first news conference on Friday, a week after 20 children and six adults were shot dead at Sandy Hook Elementary School in Newtown Connecticut.
Adam Lanza, 20, carried out the attack on 14 December after killing his mother. He later shot himself dead.
The head of the NRA criticised violent video games and films, and said his group will develop a national security programme for schools.
Chief executive Wayne LaPierre called for a national database of the mentally ill and blamed violent video games and films for portraying murder as a way of life.
He spoke out against the media for demonising lawful gun owners and for suggesting a ban on certain types of weapon would be effective, the BBC reports.
"The only thing that stops a bad guy with a gun is a good guy with a gun," he said.
Congress should authorise funding for armed security in every school in the country, he said, adding that an "extraordinary corps" of trained professionals could be drawn from active and retired police officers, security professionals and firefighters around the country.
The news conference was interrupted twice by protesters carrying banners who accused the National Rifle Association of contributing to the violence that killed the children.
New York's mayor, Michael Bloomberg, says the NRA's response is "a paranoid vision of a dangerous and violent America where everyone is armed and no place is safe".
The school shootings have prompted some pro-gun congressmen to change their views on regulation.
A California Senator, Dianne Feinstein, says she will introduce legislation on tighter gun control laws in the new year.
Bells in Newtown tolled 26 times on Friday as the state marked a week after the shootings.
The governor of Connecticut asked people throughout the state to join a moment of silence, and churches in many other states also rang their bells 26 times.
Funerals for those killed have taken place throughout the week, and continued in Newtown on Friday.
In Pennsylvania, four people died on a highway on Friday when a gunman shot dead three people and later was killed in a shootout with police, Reuters reported.