The break-in happened sometime late the evening of Dec. 7 or early the morning of Dec. 8 at Cambridge Elementary School at 1135 Lacey Lane, Hughes said.
The intruders shattered windows to gain access to two classrooms at the school and stole computer equipment. In one of the classrooms, one or more of the suspects also urinated on the floor, Hughes said.
Whether the urine was an act of vandalism was not immediately clear, but Hughes said the behavior was "consistent with someone who would steal from a school, which is essentially stealing from children."
Hughes estimated that the loss to the school is more than $1,000.
The school is equipped with an alarm, but for some reason the alarm did not go off during the break-in.
As of this morning, detectives still had no clear leads in the case. Investigators are urging anyone with information about it to call the Concord Police Department at (925) 671-3030. People who wish to remain anonymous can call the Police Department's tip line at (925) 603-5836.