Associated Press

NEWTOWN, Connecticut (AP) _ Children in a school bus pressed their faces to the windows as they watched mourners gather Tuesday for two more 6-year-olds killed in last week’s Connecticut school shooting. Most students returned to school for the first time, as the toll of funerals for the 28 dead continued on a gray, wet day.

The national debate on gun control sharpened as a prominent private equity firm said it would sell the country’s largest firearms manufacturer, calling Friday’s mass shooting, one of the worst in U.S. history, a “watershed” moment. In Washington, President Barack Obama signaled support for efforts to reinstate an assault weapons ban.

Security remained high in Newtown, and the small, affluent community was still on edge as the rest of the country prepared for the Christmas holidays. Funerals were held for 6-year-old James Mattioli and Jessica Rekos, among the 20 young students killed. All were 6 or 7 years old.

“There’s going to be no joy in school,” 17-year-old Newtown student P.J. Hickey said. “It really doesn’t feel like Christmas anymore.” But he added, “This is where I feel the most at home. I feel safer here than anywhere else in the world.”

In a sign of investors distancing themselves from U.S. gun makers, private equity firm Cerberus Capital Management announced it would sell arms manufacturer Freedom Group, which makes the rifle thought to have been used in Friday’s rampage.

The mystery of why a smart but severely withdrawn 20-year-old, Adam Lanza, shot his mother to death in bed before rampaging through Sandy Hook Elementary was as deep as ever. The school will remain closed indefinitely.

A Connecticut official said Nancy Lanza, a gun enthusiast who practiced at shooting ranges, was found dead in her pajamas, shot four times in the head with a .22-caliber rifle.

Investigators say Lanza had no ties to the school he attacked, and they have found no letters or diaries that could explain why he targeted it. He forced into the school shortly after its front door locked as part of a new security measure. He wore all black and is believed to have used a Bushmaster AR-15-style rifle, a civilian version of the military’s M-16. Versions of the AR-15 were outlawed in the U.S. under the 1994 assault weapons ban, but the law expired in 2004.

Debora Seifert, a spokeswoman for the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, said both Lanza and his mother fired at shooting ranges and visited ranges together.

“We do not have any indication at this time that the shooter engaged in shooting activities in the past six months,” Seifert said.

In Washington, White House spokesman Jay Carney said Obama spoke Tuesday with Sen. Joe Manchin, a conservative Democrat and avid hunter who is now supportive of a national discussion on preventing gun violence.

“This awful massacre of our youngest children has changed us,” Manchin has said.

Carney also said Obama would support legislation to close the gun show “loophole,” which allows people to buy guns from private dealers without background checks.

The U.S. Conference of Mayors wrote Obama and Congress calling for a ban on assault weapons and other high-capacity magazines like those used Friday, a strengthening the national background check system and a strengthening the penalties for straw purchases of guns, in which legal buyers acquire weapons for other people.

House Republicans discussed the gun issue at their regular closed-door meeting Tuesday, and at least some were willing to consider gun control as part of a solution to the kind of violence seen Friday.