NEWTOWN, Conn. -- The bells of Newtown tolled Friday morning to mark one week after the second-deadliest school shooting in U.S. history, ringing 26 times to remember each child and staff member killed. Nationwide, other churches and communities did the same, and President Barack Obama at the White House observed a moment of silence.

The observances ignored the first victim of 20-year-old gunman Adam Lanza: his mother, Nancy, who was shot in the head four times while she lay in bed.

Her death makes 27 killed.

A private funeral was held Thursday in New Hampshire for Nancy Lanza, according to Donald Briggs, the police chief in the town where her funeral was held. About 25 family members attended.

In Newtown, where makeshift memorials of stuffed animals, angels, candles, flowers and balloons are found throughout town, there is only one noticeable tribute to Nancy Lanza. It's a letter written by a friend and shellacked onto a piece of wood.

"Others now share pain for choices you faced alone; May the blameless among us throw the first stone," it reads in part.

Authorities have said Adam Lanza used the guns his mother kept at their home to carry out the rampage. In a small town where multiple funerals have taken place each day, many are angry at Nancy Lanza for not keeping her guns away from her son.

Others think Nancy Lanza was an innocent victim, one who should be included at memorials.

"It's a loss of life and, yes, her life mattered," said resident Christine Lombardi. "Yes, I do believe she should be included."

The Newtown area held a fourth day of funerals Thursday as mourners laid to rest Catherine Hubbard, Benjamin Wheeler, Jesse Lewis and Allison Wyatt, all 6 years old; and Grace McDonnell, 7.

Services elsewhere were held for teachers Anne Marie Murphy and Lauren Rousseau.

On Friday, five funerals or memorials were planned.

The Obama administration will push to tighten gun laws in response to the shooting, Vice-President Joe Biden said Thursday. Biden, who is overseeing the administration's response to the shooting, said he and Obama are "absolutely committed" to curbing gun violence in the United States.

"Even if we can only save one life, we have to take action," he said.