AT least 27 people, including 18 children, have died in a school shooting in the US state of Connecticut.

The gunman was killed and apparently had two guns, a person with knowledge of the shooting said.

Officials said 27 people have died, including 18 children, in the incident at Sandy Hook Elementary School in Newtown.

It is not yet known how many more have been injured.

A member of staff at the Newtown Volunteer Ambulance Corps said a teacher had been shot in the foot and had been taken to Danbury Hospital.

The superintendent's office said the district had locked down schools in Newtown, in western Connecticut, about 60 miles north-east of New York City.

A photograph posted by The Newtown Bee newspaper showed young students - some crying, others looking frightened - being escorted by adults through a car park in a line, with hands on each other's shoulders.