Five recently graduated high school students have been arrested in connection with pyrotechnic devices found at Wayne Valley High School in mid-June that led to the school's evacuation one day before the start of final exams.

Chief Assistant Prosecutor James Wilson said four 18-year-olds and one 17-year-old — all men — were taken into custody between Tuesday night at 7 p.m. and Wednesday morning 2:30 a.m.

Wilson would not give any further details of the students, including their names or the specific charges they're facing, pending a news conference later Wednesday.

The devices were found after a student noticed their fuses hanging from a locker.

The student notified school officials, who noticed similar material coming out of a second locker.

Four bundled devices, made up of 5- to 6-inch long sticks, were removed by a bomb squad and detonated in a safe area on June 13.

Officials described the bundled sticks as "pyrotechnic devices," but not dynamite or fireworks.

Surveillance tapes from the high school showed two hooded people in the evening of June 12 putting the devices into two lockers as they walked around the second floor of Wayne Valley High School. The face of one person is obscured by what appears to be a white ski mask; the other appears to be talking on a hand-held phone.

Passaic County authorities formed a joint task force to find the suspects.

About 1,400 students were evacuated after the suspicious devices were found in the lockers on the second floor.

Finals resumed at the school, about 20 miles northwest of New York City, the day after the evacuation.