A gas leak forced the evacuation of San Andreas Elementary School on Wednesday.

Pacific Gas and Electric Co. received a call at about 11:10 a.m. regarding a leaking gas line on the 300 block of Neilsen Road, a little less than a mile from the school, according to PG&E spokesman J.D. Guidi.

A gas service representative arrived at the scene about 20 minutes later and was able to pick up a "very small reading" of gas, Guidi said.

PG&E crews arrived shortly after and began working on the leak, but fire personnel ordered the evacuation of the nearby elementary school at about 1:40 p.m., according to school officials.

Guidi said there was one-way traffic control in the area because crews had to excavate part of the road while searching for the leak.

Six customers were left without gas service in the area. Crews expected to have the line repaired by nightfall, Guidi said.

About 320 students and 20 school employees walked to the Calaveras High School, 350 High School St., about a mile away for parents or transportation, said Calaveras Unified School District Superintendent Mark Campbell.

Buses were deployed and quickly took most of the students to their homes, while others waited in the high school's after-school program for their parents to pick them up, Campbell said.

Only a few students were left at the high school by 4:30 p.m. but their parents were en route, according to district administrative assistant Shirley Bell.

Bell said she was still awaiting confirmation that the leak had been fixed before calling parents to let them know whether classes would be held Thursday.

The Calaveras County Sheriff's Office warned residents in northwest San Andreas they may hear a loud noise similar to a jet engine while PG&E relieved pressure from a gas main in the area each morning from 5 to 8 a.m., Sept. 18 to 20.

PG&E officials couldn't confirm Wednesday evening whether the leak was related to the other work.