Gunmen on motorbikes in India’s West Bengal ambushed and killed a political aide from the ruling Hindu-nationalist party days after it swept state elections, police said on Thursday.

Prime Minister Narendra Modi’s Bharatiya Janata Party (BJP) won a resounding victory on Monday in the eastern state of more than 100 million people, taking 207 of the 294 assembly seats, for its first-ever state victory in West Bengal.

Chandranath Rath, 41, a close aide of West Bengal’s BJP chief Suvendu Adhikari, was shot dead late on Wednesday near his home in Kolkata.

Adhikari, the leader of the opposition in the state assembly, now tipped to become the state chief minister, called it “cold-blooded murder”.

Motorbikes blocked Rath’s vehicle, before the attackers opened fire in a barrage of around a dozen shots, hitting him multiple times in the heart.

“The shooting happened at about 11pm on Wednesday – the bikes that stopped Rath’s car have been seized,” West Bengal police chief Siddh Nath Gupta said.

“The bikes had fake registration numbers, and we are looking for the assailants.”

Pritam Sengupta, a doctor at Apollo Hospital, said Rath was “brought dead with multiple bullet injuries in his chest”.

The killing brings the total killed since the results were announced on Monday to at least five. Hundreds have been arrested in post-election violence over the past few days.

Trading blame

West Bengal had been ruled by Modi’s fierce critic and adversary, Mamata Banerjee, as chief minister since 2011.

Banerjee, leader of the regional All India Trinamool Congress (TMC), also lost her seat in the poll and has rejected the results.

Analysts say the BJP’s victory in the largely Bengali-speaking state is one of its most significant since Modi was first elected prime minister in 2014, expanding its dominance beyond the Hindi-speaking heartland of north and central India.

The killing has added to political tensions in the state, with the BJP and TMC trading accusations over the deaths since the results.

“It was a planned murder,” BJP’s West Bengal president Samik Bhattacharya said.

“This is expected from Trinamool Congress,” he alleged. “They are responsible for this death.”

The TMC rejected any role in the shooting, but accused the BJP of targeting their supporters.

“We strongly condemn the brutal murder of Chandranath Rath,” the party said in a statement, adding that it also condemned attacks on TMC members “allegedly carried out by BJP-backed miscreants”.

The BJP said it would swear in its leader as chief minister on Saturday.

West Bengal has a history of post-election ‌violence, and about ‌a dozen people were killed during similar clashes between political parties after results were declared during the previous poll in 2021.

Additional reporting by Reuters