A law firm representing the families of nine of the 26 people killed and a teacher injured at the Sandy Hook Elementary School in Newtown on Dec. 14, 2012 says it has filed a lawsuit against the manufacturer, distributor and seller of the rifle used in the shooting.

The negligence and wrongful death lawsuit asserts that the Bushmaster AR-15 rifle should not have been made publicly available because it is a military weapon unsuited for civilian use.

It goes on to say that the "number of lives lost in those 264 seconds was made possible by the shooter's weapon of choice: a Bushmaster AR-15 rifle, model XM15-E2S."

The lawsuit has been filed against Bushmaster Firearms, which is also known as Remington Outdoor Group, as well as Camfour, a firearm distributor, and Riverview Gun Sales, the store where the Bushmaster rifle was purchased in 2010.

Remington released a statement saying company officials do not comment on pending litigation.

Messages the Associated Press left, seeking comment from the other defendants were not immediately returned

"The AR-15 was specifically engineered for the United States Military to meet the needs of changing warfare," Josh Koskoff of Koskoff, Koskoff & Bieder, the Connecticut law firm representing the families, said in a news release. "In fact, one of the Army's specifications for the AR-15 was that it has the capability to penetrate a steel helmet. This weapon was not designed for home defense or hunting. This weapon was designed to efficiently kill other human beings in combat."

The lawsuit makes mention of unstable people having access to AR-15 weapons, which were used to carry out mass shootings.

"Time and again, mentally unstable individuals and criminals have acquired an AR-15 with ease, and they have unleashed the rifle's lethal power into our streets, our malls, our places of worship, and our schools," the lawsuit says.

Probate records from earlier this month show that parents of 10 of the 20 first-graders killed in the school shooting have created estates for the children, which are required to file such lawsuits. A court clerk said at the time that most of the parents checked a box on the forms saying they intended to file wrongful death actions.

The lawsuit was filed on behalf of Donna L. Soto, administratrix of the estate of Victoria L. Soto; Ian and Nicole Hockley, co-administrators of the estate of Dylan C. Hockley; William D. Sherlach, executor of the estate of Mary Joy Sherlach; William D. Sherlach, individually; Leonard Pozner, administrator of the estate of Noah S. Pozner; Gilles J. Rousseau, administrator of the estate of Lauren G. Rousseau; David C. Wheeler, administrator of the estate of Benjamin A. Wheeler; Neil Heslin and Scarlett Lewis, co-administrators of the estate of Jesse Mccord Lewis; Mark and Jacqueline Barden, co-administrators of the estate of Daniel G. Barden; Mary D'avino, administratrix of the estate of Rachel M. D'avino; and Natalie Hammond.

The 40-page complaint was filed in superior court in Bridgeport.