A 225-page study commissioned by the National Rifle Association has endorsed and amplified the gun rights group's immediate response to the mass killing in Newtown: that all schools in the United States should have police or armed staff members trained to confront a shooter.

Although ostensibly independent of the NRA, the examination of school safety issues, released Tuesday, provides the organization with an alternative narrative to the various gun-control measures on Capitol Hill that it is opposing or seeking to dilute.

The National School Shield Report focuses on a host of possible safety measures, such as internal door security and perimeter fencing, but its central recommendation is that armed personnel should be posted in all schools.

Former congressman Asa Hutchinson, a Republican, who led the $1 million study, said that schools could use "school resource officers" - typically local police trained to work in schools - or arm teachers or administrators designated by school boards or superintendents.

Those staff members should receive 40 to 60 hours of weapons instruction and other training, the report recommends.

In a statement, the NRA said it needs time "to digest the full report" but thinks it will "go a long way to making America's schools safer."

Hutchinson argued that armed school personnel can reduce death tolls in shootings. And he pointed to a 1997 incident at a high school in Pearl, Miss., in which an assistant principal was able to retrieve a .45 semiautomatic pistol from his truck and detain a 16-year-old student who had killed two students and wounded others.

"The key is reducing that response time," Hutchinson said.

The proposal has drawn a mixed reaction from school districts, and critics have argued that putting armed personnel in schools would increase the risk of shootings.

"Today's report is nothing more than a continuation of the NRA's attempts to prey on America's fears, saturate our schools with more guns and turn them into armed fortresses," Marian Wright Edelman, the president of the Children's Defense Fund, said in a statement Tuesday. "It must be soundly rejected."

The report does not provide specific recommendations for the ratio of armed personnel to students or what kind of guns school personnel should carry. Hutchinson said those are local decisions, but weapons could include handguns, shotguns or semiautomatic rifles.

Hutchinson said that many smaller school districts cannot afford school resource officers and that their only option is to train existing staff in how to respond to a shooter.

Mark Mattioli, whose 6-year-old son, James, was killed in Sandy Hook Elementary School in Newtown in December, appeared alongside Hutchinson at a news conference and said he applauded the report's recommendations.

"I'm putting it on you, I'm putting it on the experts out there to do something with these recommendations, to implement solutions, so people don't have to go through what I'm going through," Mattioli said.

Hutchinson generally declined to be drawn on the merits of particular elements of current gun control legislation, but he said the measure just approved by the state of Connecticut, which extends its ban on assault weapons and imposes registration requirements for high-capacity magazines, would do nothing for school safety.

"I would say it's totally inadequate," said Hutchinson, who said banning certain kinds of weapons wouldn't stop a shooter from entering a school with another kind of gun. "You can add assault weapons and it doesn't stop . . . violence in the schools."

Rep. Elijah Cummings, a Democrat, who is sponsoring a federal gun-trafficking bill, said he was skeptical about armed guards in schools.

"Having more guns in schools, I don't think, is necessarily the answer," said Cummings, who spoke at the National Press Club just before Hutchinson began his news conference in a nearby room. "But any jurisdiction that wants to take care of their kids in that way, I think that may not be a bad proposal. But keep in mind that gun violence is not restricted to schools."

Cummings said he hopes that the NRA will reconsider its objections to federal gun-trafficking legislation, which would impose stiff punishments on people who sell guns to criminals. The NRA is circulating alternative language that would require law enforcement officials to prove that a straw purchaser knew that the person he was buying the gun for was prohibited by law from owning a firearm, a requirement that would gut the bill, its supporters say.

"I would hope that our friends in the NRA would reconsider that," Cummings said. He added, "There are only two groups that should oppose this bill: criminals and people who want to buy guns for criminals."