NEW YORK (CBSNewYork) -- At least two bomb threats were called into NYPD precincts in New York City Tuesday, sources said.
The threats were called into the 75th Precinct in East New York and 104th Precinct in Queens, sources told CBS2.
Both buildings were swept by the bomb squad and cleared, sources said.
While police investigate the origin of the threats, security has been stepped up at all station houses following the fatal shooting of on-duty NYPD officers Rafael Ramos and Wenjian Liu on Saturday.
Earlier Tuesday, Mayor Bill de Blasio observed a moment of silence for the fallen officers at City Hall at 2:47 p.m. — the time Liu and Ramos were killed.
De Blasio has called for a moratorium on protests and political rhetoric surrounding the Eric Garner and Michael Brown grand jury cases in the wake of the officer deaths.
But some protesters took to the streets Tuesday night anyway, chanting "How do you spell murderers? NYPD!" and "Indict, convict, send those killer cops to jail. The whole damn system is guilty as hell," CBS2's Tony Aiello reported.
It remains unclear if the bomb threats have any connection to the protests over the Garner case.
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