Police on school grounds in the Los Angeles suburb of Compton are to be armed with semi-automatic AR-15 assault weapons in an attempt to prevent future school massacres.
The decision came after officers said they were not well enough equipped to deal with any attacker wielding a rifle with high capacity magazines and wearing body armour, as has been the case in several recent US school shootings.
Using semi-automatic weapons would allow them to penetrate body armour and to be more accurate than when firing with handguns, police said.
Compton, a suburb of 100,000 people in southern Los Angeles, has long been associated with gang and gun culture, although the murder rate has dropped dramatically in recent years.
The local school board, which oversees 26,000 pupils, decided to allow specially selected officers to carry the AR-15s in the back of their cars after having training.