A 13-year-old US boy carrying a replica assault rifle has been shot dead by police in the US state of California.

Officers in the city of Santa Rosa say they opened fire after the boy refused orders to drop the rifle, which they believed to be real.

This incident is said to have happened a day after a 12-year-old boy in Nevada shot dead a maths teacher at his school and wounded two fellow pupils before taking his own life.

In the latest incident, two sheriff's deputies saw the teenager "with what appeared to be some type of rifle".

The deputies called for backup and repeatedly ordered the boy to drop the gun before firing several rounds from their handguns, police is report to have said.

However, the boy, who was pronounced dead at the scene, was said to have been identified by his family as Andy Lopez.