SAN DIEGO -- Prosecutors declined Tuesday to file charges against an 18-year-old scholar-athlete accused of setting off five bottle bombs at San Ysidro High School last week, citing the need for more investigation.

Elphbert Laforteza, a senior, was booked into jail Friday night hours after the bottle-bombs went off in trash barrels during lunch.

He will be released from custody pending further investigation, said spokesman Paul Levikow of the San Diego County District Attorney's Office.

More arrests are anticipated and charges could be brought at a later date, Levikow said.

Besides the five crude homemade chemical bombs that exploded, three others were disabled by the bomb squad and officers found four others partially assembled in Laforteza's backpack, according to authorities.

Nobody was injured and no property was damaged in the explosions.

Laforteza told investigators he had brought a dozen of the bottle bombs to the Airway Road campus, said Maurice Luque, a spokesman for the San Diego Fire-Rescue Department.

Laforteza was an all-league football player and an ROTC cadet. He had applied but had not been admitted to the Air Force Academy, a spokesman for the Air Force said.

San Ysidro High Principal Hector Espinoza said Laforteza will receive his diploma but will not be allowed to graduate with his class on Thursday.