Thorough searches were carried out at the Income-tax office in Surat after a bomb scare created panic in the six-storey building on Monday, police sources said.
According to the police, an anonymous caller had rung up Income-tax department public relations officer RD Meena and told him about a bomb being placed in the building.
Dog squads and bomb disposal squads were rushed to the spot and a thorough search was conducted.
However, no explosive was found.
Police are now trying to trace the identity of the caller, sources added.
Last week, a similar hoax call was received by the police in Nadiad about a bomb being planted in the district court premises.