CPI (M) city president Ajit Abhyankar told PTI that the parcel was received yesterday, but it was opened by one of the office-bearers late this evening.
It contained a plastic box. "While opening it we sensed something suspicious and immediately alerted the police and bomb detection and disposal squad," he said.
ACP Sharad Ugale said the box was found to contain a detonator, batteries and some white powder.
"Besides, there was a threat letter which said the CPI (M) office will be blown off," he said.
Last year, the city-based Film and Television Institute of India and a journalism college had received similar parcels.
Disclaimer: No Business Standard Journalist was involved in creation of this content