FREMONT (CBS SF) — Authorities are investigating more anonymous bomb threats made against schools in the Fremont Unified School District, police and district officials said Tuesday.

The latest threats were made late Monday and early Tuesday following threats that were received last week against 13 schools.

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On Tuesday morning, 10 schools in the district were the target of threats, which are not credible, police and school officials said.

District Superintendent CJ Cammack said in a letter Tuesday morning to the school community that the threats made Tuesday are the same or similar to the ones last week. The threats were made by email.

The schools targeted by threats on Tuesday were the following:

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Blacow Elementary
Green Elementary
Durham Elementary
Mattos Elementary
Leitch Elementary
Parkmont Elementary
Millard Elementary
Hopkins Junior High School
Horner Middle School
Irvington High School
Kennedy High School

All students are learning from home, so they are not on any campuses, police said. Cammack said unlike last week, instruction is unaffected Tuesday.

A letter from Cammack to parents of students at the schools that received threats was posted on the Fremont Unified School District website.

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