The cache of weapons 

Brady Eggleston of Newtown participates in a protest outside the National Shooting Sports Foundation in Newtown, Connecticut, March 28, 2013. Residents began receiving robocalls from the NRA trying to enlist them in efforts to defeat new statewide gun control proposals, three months after a gunman killed 20 students and six adults at Sandy Hook elementary School in Newtown, Connecticut, Dec 14, 2012. [Photo/Agencies]

The court papers said police searching the Lanza home found an Enfield bolt-action rifle, a Savage Mark II rifle, a revolver, three samurai-style swords with blades measuring up to 28 inches (71 cm) and a 6-foot, 10-inch (208 cm) wood-handled pole with a blade on one side and a spear on the other.

They also found a smashed computer hard drive and a gun safe in the room they believed to be Adam Lanza's bedroom; NRA certificates in the names of both Adam Lanza and his mother; and Nancy Lanza's body in her bed with a gunshot wound to her forehead and a rifle on the floor nearby.

FBI agents interviewed one or more people who described Lanza as "a shut-in and avid (video) gamer who plays Call of Duty amongst other games." It was noted that the Sandy Hook Elementary School was his "life."

Mayors Against Illegal Guns on Thursday released a TV ad featuring family members of the victims calling for tighter control of guns. Broadcast in Hartford, Connecticut, it was aimed to encourage a proposed Connecticut gun-control law.

"We cannot afford to wait for another tragedy," said New York City Mayor Michael Bloomberg, the group's co-chairman.

The investigation documents were released on the same day as hundreds of protesters demonstrated at the National Shooting Sports Foundation, less than 3 miles (5 km) from the school, over the NRA's opposition to new gun control laws. Newtown residents were enraged after receiving a slew of robo-calls on behalf of the NRA that were critical of gun control laws.

Caithlin De Marrais, a 40-year-old musician from Easton, Connecticut, who brought along her 7-month-old baby, carried a handmade sign proclaiming "Enough."

"I'm here to support Newtown and all the communities that have lost loved ones due to gun violence," she said.

The crowd also included those who oppose more gun control, among them Tahra Erickson, 33, who stood with her three-year-old son Zachary.

"I don't think it's the government's job to tell me how I can protect my son," she said.