FOUNTAIN VALLEY ( — Police swarmed an Orange County high school and classes were canceled Wednesday after officials received a bomb threat that turned out to be a hoax.

Officers questioned a 17-year-old student after a Fountain Valley High School teacher received a message around 5 a.m. Wednesday from the boy’s email account. The message said explosives were planted around the campus.

“I’m the webmaster as well, so I received the email. The email came to my account,” journalism teacher Sean Ziebarth said. “It had said there had been explosives and that the person had an illegally purchased gun.”

“The email came from an active student’s email account and the email also indicated that the student would come this morning with an assault rifle and kill any surviving people on campus,” Fountain Valley police Sgt. Tony Luce said.

Huntington Beach Union School District officials notified parents of the situation and canceled classes. Classes were scheduled to resume Thursday.

The student, who officials would not identify, denied sending the email and allowed officers to search his computer and phone. Police said nothing suspicious was found during a cursory search, and the teen was not placed under arrest.

“Officers found no indication that the email had been sent from his account,” Luce said. “It’s quite possible the student’s email account was hacked.”

Police believe that whoever sent the message meant it as a hoax.

Investigators plan to conduct a deeper probe into the student’s devices and they’ll use computer forensics to determine the origin, or IP address, of the email.

The high school, at 17816 Bushard St., and surrounding areas were evacuated as a precaution. The Orange County Bomb Squad was dispatched to the school, but by 10 a.m., no explosive devices were located and the campus was cleared, according to officials.

“When I heard what was in the email I was a little bit scared because the description was very graphic, and I just didn’t like that at all,” Fountain Valley H.S. student Kris Nguyen said. “At first, I was kind of scared, because I’ve seen the news about previous problems that have happened at other high schools in the United States.”