Gadricholi, Maharashtra: A CRPF battalion on election duty when the explosion took place.

A Central Reserve Police Force (CRPF) trooper was critically injured in an improvised explosive device (IED) blast in Maharashtra's Maoist-affected Gadricholi district on Wednesday, a day before voting in the area for Lok Sabha polls.

The blast took place in Gatta-Ettapalli area in the evening where the troops of the 191st battalion were on patrol.

The paramilitary trooper was part of a team sent to secure the area on the eve of the elections, an official said.

He is said to be in critical condition and is being airlifted for treatment.

The region will vote in the first phase of Lok Sabha elections on Thursday.

A BJP legislator and four security personnel were killed in a Maoist-triggered IED blast in Chhattisgarh's Dantewada district on Tuesday.