PINOLE, Calif. -- Police arrested two teenagers Friday afternoon in connection with a gun scare at Pinole Valley High School.

One of the arrestees had drugs and the other is connected to the gun scare, police officials said. The gun has not been recovered, but police said they are convinced the reports of a gun on campus were accurate.

The incident began when a student told school staff at Pinole Valley High School that he had seen another young person with a sawed-off rifle while on the way to school on an AC Transit bus, according to Paul Ehara, the Director of Communication for the school district. The Pinole Police Department was called immediately by staff.

"Police got a description of the young person who allegedly had the weapon and asked the school to secure the students in their classrooms," explained Ehara. Police then conducted a room-to-room search based on that description. A Coast Guard Helicopter provided air support.

KTVU spoke with one student by cell phone who described police entering his classroom and searching two students.

"At first, police were saying that they were training," said 16-year-old Javari Jackson. "Then we say some cops loading their guns, and we new it wasn't a drill. They came into the class and searched two guys; checked their arms for tattoos and searched them."

Pinole Valley High School students were being evacuated classroom by classroom onto Western Contra Costa Transit Authority buses headed to Collins Elementary School, located at 1224 Pinole Valley Road, a West Contra Costa Unified School District spokesman said.

A secretary at the elementary school, Pam Porter, said the evacuations started around 10:30 a.m.

Parents were able to pick up their children from Collins Elementary as soon as they arrived, she said. District spokesman Paul Ehara said that students whose parents could not immediately pick them up were released from the elementary school at the end of normal summer school hours at 1:50 p.m.

According to Ehara, the report of a student with a gun was first made at the high school at 2900 Pinole Valley Road at about 8:10 a.m. by a fellow summer school student who took an Alameda-Contra Costa Transit District bus to school.