SARATOGA (CBS SF) — No bomb was located at West Valley College in Saratoga after a bomb threat Tuesday morning caused an evacuation and the cancellation of all classes for the rest of the day.

Campus police along with Santa Clara County Sheriff’s deputies and a bomb-sniffing dog searched the campus, located at 14000 Fruitvale Ave., for about four hours but were unable to locate a bomb, according to West Valley College spokesman Scott Ludwig.

Around 9 a.m., a student reportedly found a letter somewhere on campus mentioning a bomb in one particular part of the school.

The student then informed a school staff member, who reported it to the school’s administration. After reviewing the letter, campus police determined the threat was credible and decided to evacuate the school, Ludwig said.

The school plans on reopening Wednesday, according to Ludwig.

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