Karnataka's state elections are scheduled for May 5, so a police van was posted outside the BJP branch in Malleshwaram, a crowded residential neighbourhood which also hosts several temples.
Intelligence officials told NDTV that an Improvised Explosive Device (IED) was used this morning, but were not clear on how the bomb was triggered. A large fire followed the explosion. Several vehicles including the police van were gutted.
Bangalore Commissioner Raghavendra Auradkar said the explosives appear to have been placed on a motorcycle, but so far, he said, there are no details of the sort of material that was used.
Karnataka's Home Minister R Ashok described the blast as "terrorist activity" and said BJP workers were the target. (Watch)
The policemen who were injured today were on duty on a day when a lot of activity was expected at the BJP office because it is the last day for candidates to file their nomination papers for the state elections.
"The injuries are not very serious and nobody is critically injured, said L Pachau, the Director General of Karnataka.
He said, "The Home Ministry will provide any assistance that the Karnataka Police needs."
Union Home minister Sushil Shinde has said the centre would begin an inquiry into the incident. When asked if this could be described as a terror attack, he said that would be known only "after the probe was completed."
A team from the National Investigation Agency, which has expertise in handling terror attacks, has inspected the site.
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