According to local district officials, the Maoist cadres forced a UML cadre out of the office before pulling down the shutter and breaking a few chairs.
They ran away after police reached the scene.
Maoist cadres on Tuesday had threatened UML and Nepali Congress to leave the district within 5 days.
A government security committee is holding a meeting to review the security situation in the district.
Members of NC and UML are forced to hide, the local officials said.
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