Plastic bottle explosives shut down school

(CNN) - Police were questioning an 18-year-old San Ysidro High School student Friday after as many as 13 explosive devices were found at the school, a San Diego fire department spokesman told CNN.

The fire department arrived at the school at 3 p.m., said Maurice Luque, after six devices, constructed in plastic bottles exploded. A search turned up seven more bottles, he said.

The bottles contained acid and another substance, which he said he would not identify, and were designed to explode.

Authorities put the school on lockdown for an hour. Friday was the last day of classes for the year, Luque said. The fire department was making another sweep of the school to search for any additional devices.

Luque said the unnamed teenager could face 13 felony counts of possession and use of a destructive device and another 13 counts of possession of bomb-making materials.