FOUNTAIN VALLEY, Calif. (KABC) -- Classes were canceled at Fountain Valley High School Wednesday after a bomb and shooting threat was emailed to the school.



A bomb squad searched the campus, but no explosives were found.



Authorities said the principal called police at 6:15 a.m. about an email that claimed bombs were placed all over the school. The email came from a student's account and was sent at about 10 p.m. Tuesday, investigators said.



The email also stated that the student was going to bring an assault rifle to campus to kill anyone who survived the blasts.



The school was immediately placed on lockdown, and faculty members who were already on campus were evacuated. Students were alerted that classes were canceled.



Police interviewed the 17-year-old student at his house and found no evidence yet that the email came from him directly. Authorities also said the student does not appear to have access to weapons.



"The student indicated that he did not send the email. He has allowed officers to look at his phone and his computer," said Sgt. Tony Luce of the Fountain Valley Police Department.



Officers said they will conduct further forensics on the student's computer. They also haven't ruled out the possibility that someone else may have hacked into the teen's email and sent the threat.



The campus reopened to faculty and extracurricular activities at about 11:30 a.m., and officials said classes will remain canceled until Thursday. Fountain Valley police will have increased patrols at all Fountain Valley schools for the next few days.



In Costa Mesa, California Elementary School was evacuated for a short time just after 11 a.m. after someone called in a threat, claiming that a jet fighter was going to attack the school. The threat was deemed not credible.



