The blast inside a plastic factory at Sujapur area of Malda district took place at around 11:30 am, the police said.
Four factory workers were killed on the spot and one was brought dead to the hospital. Five others were critically injured in the explosion that ripped apart the building, a police official said.
One of the five injured died later when he was being shifted to a hospital in Kolkata. The death toll is now six, a senior district official told PTI.
Preliminary investigation has found that a technical fault in a heavy machine inside the factory caused the high intensity blast, Malda superintendent of police Alok Rajoria said.
"The explosion took place during plastic manufacturing. We are probing all the angles and a forensic team will visit the spot," he said.
A huge police contingent has been posted at the spot to keep the situation under control, the officer said.
State minister Firhad Hakim has been sent to Malda to take stock of the situation.
The state government has announced an ex-gratia of Rs two lakh for the kin of each deceased and Rs 50,000 for each injured person.
Governor Jagdeep Dhankhar, who has been at loggerheads with the TMC government since he assumed office over a year ago, expressed anguish over the incident and asked Chief Minister Mamata Banerjee to "contain illegal bomb- making" and ensure "professional non-partisan investigation".
"Anguished at deaths in reported blast that ripped establishment apart at Sujapur area of Malda district. Time @MamataOfficial to proactively contain illegal bomb- making and ensure professional non-partisan investigations @WBPolice," he tweeted.
The governor also asked the administration to ensure medical assistance to the injured.
His comment drew a sharp retort from the home department which tweeted "The Malda Sujapur plastic factory accident today is related to manufacturing process issues and has got nothing to do with illegal bomb-making, as suggested non- responsibly by some quarters."
It also said, "DM and the SP on spot have been reporting to state officers after urgent inquiries, and compensation steps have been taken. A senior Minister has flown to site, and it is time to be factually correct. Government is helping the victims and their families".
Dhankhar shot back saying that law and order and state of investigations are "worrisome and call for non- partisan handling".
"And now @HomeBengal judgmental even with five deaths, many injured, establishment ripped apart & more underground "non-responsibly by some quarters". Why not @WBPolice investigate professionally! Why not reveal @MamataOfficial the number of deaths in such bomb explosion!" Dhankhar posted in the micro blogging site.
The governor referred to his previous showdown with the state home department over the statistics of rapes and kidnappings and time has come for it to behave responsibly.
"High time for ACS (additional chief secretary) Home who is responsible for @HomeBengal to respond to pending issues from my end. Indiscriminate and untenable stance qua Governor cannot be overlooked. Law and order, state of investigations are worrisome and call for non-partisan handling @MamataOfficial," he said in a series of tweets.
The incident also triggered a war of words between the BJP and TMC, with the saffron party demanding NIA probe into the incident.
"Bomb blasts have become a regular affair in West Bengal. Every other day,there is an incident of a bomb blast in the state. We demand an NIA probe in the Malda blast incident," BJP national general secretary and Bengal minder Kailash Vijayvargiya said.
"We will write to the union home ministry requesting it for an NIA probe to bring out the truth as the state police will try to hush up the matter," he said.
Refuting the charge, Hakim said "We respect central agencies but the BJP should stop using them for their vested political interests. BJP should stop doing politics over dead bodies".
The state police is probing the incident, he added.
(Only the headline and picture of this report may have been reworked by the Business Standard staff; the rest of the content is auto-generated from a syndicated feed.)
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