Staffers at a Brooklyn charter school have been bombarded with racist emails — as well as threats to bomb and shoot up their building, NYPD sources told The Post on Tuesday.

A 41-year-old employee at Achievement First High School in Bushwick said she received a threatening email from an unknown sender at 9:40 a.m. telling her to go back to Hong Kong, sources said.

The nasty missive also asked the shaken staffer if her eyes were closed or open, according to sources.

Additional anti-Asian emails were fired off to other staff members at the charter school on Starr Street, the complainant told police.

The messages warned that the unidentified sender planned to strafe their building with gunfire and detonate a bomb at some point during school Tuesday.

Police are investigating the incidents as terroristic threats.

Achievement First currently runs 23 schools in New York City and also operates in Rhode Island and Connecticut.