A jawan of the Central Industrial Security Force and four civilians were killed on Thursday when suspected Maoists triggered a blast on a bus in poll-bound Chhattisgarh’s Dantewada district, ANI reported.

Dantewada Superintendent of Police Abhishek Pallava said two personnel of the Central Industrial Security Force were injured in the incident, PTI reported.

Pallava said the explosion took place in a hilly area in Dantewada’s Bacheli. The CISF personnel were returning to their camp from the market when the bus exploded. The bus driver, conductor and the cleaner were killed in blast along with the CISF jawan. Security forces have begun a combing operation in the area to apprehend the suspected rebels, NDTV reported.

The CISF personnel were deployed in the area for the first phase of Assembly elections in the state on November 12. The second phase of the polls is on November 20.

“The morale of the forces will not be affected by such attacks,” said Bastar Inspector General of Police V Sinha. “The upcoming Assembly elections will be conducted peacefully.”

Prime Minister Narendra Modi and Congress President Rahul Gandhi are scheduled to campaign in the state on Friday, News18 reported. Modi will address an election rally in Jagdalpur, while Gandhi will address five rallies over two days, including in Rajnandangaon, Chief Minister Raman Singh’s constituency.

On Wednesday, the Election Commission had asked neighbouring Odisha to seal its border with Chhattisgarh and increase monitoring. The poll panel asked administrations in eight border districts in Odisha to increase monitoring to detect Maoists or people carrying alcohol, cash and other materials.

On October 30, Doordarshan video journalist Achyutanand Sahu was killed along with three policemen in a Maoist ambush in Dantewada district. The banned Communist Party of India (Maoist) claimed they did not know a journalist was travelling with the police party.