NEWTOWN, Conn. (CBS/AP) ? At least 26 people were killed following a shooting at an elementary school in Newtown, Connecticut on Friday, according to multiple reports.

In a news conference, officials said they would not confirm the number of victims until the families were notified.

However, according to CBS News and the Associated Press, both citing law enforcement officials, said 18 children are among the dead.

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The gunman opened fire at Sandy Hook Elementary School in Newtown around 9:30 a.m.

Connecticut State Police Lt. Paul Vance said along with local police, all on and off-duty troopers were called to respond to the scene.

They swarmed the school immediately when the arrived.

Lt. Vance confirmed that the shooter is dead inside the school. Earlier, reports said at least 27 people were dead. It appears that number included the shooter.

John Miller reports that the gunman who was killed appears to have traveled from New Jersey. A law enforcement official told the AP the attacker is a 20-year-old man with ties to the school.

The shooter apparently had two guns, a person with knowledge of the shooting told the AP.

An official told the AP that a gun used in the attacks is a .223-caliber rifle. The official also said that New Jersey state police are searching a location in that state in connection with the shootings.

CBS News correspondent Jon Miller says preliminary reports from officials indicate that police have discovered an additional body at home connected to suspected shooter.

It is unclear what the shooter’s motive may have been.

The superintendent’s office said the district had locked down schools in Newtown, about 60 miles northeast of New York City. Schools in neighboring towns also were locked down as a precaution.

Photos from the scene showed young students ? some crying, others looking visibly frightened ? being escorted by adults through a parking lot in a line, hands on each other’s shoulders.

Connecticut’s governor was on the scene in Newtown. The White House said President Barack Obama was notified of the shooting and was receiving updates.

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