Kolkata, May 14 (IANS): In the wake of violence surrounding the West Bengal rural polls, a CPI-M activist and his wife were burnt to death in their house allegedly by a group of miscreants backed by the Trinamool Congress in South 24 Parganas district's Namkhana, the Left party said on Monday.

Police also confirmed that the couple died in the fire but said the cause is still to be ascertained.

"The residence of Debu Das of Budhakhali Gram Panchayat in Namkhana was allegedly torched by the Trinamool Congress workers on Sunday midnight," a Communist Party of India-Marxist (CPI-M) member said.

Both Das and his wife were killed in the fire, a release issued by the CPI-M's South 24 Parganas district Secretary Shamik Lahiri said.

The party also alleged that Das was threatened by Trinamool Congress candidate Amit Mondol and his associates of dire consequences earlier on Sunday.

The Left party urged the State Election Commission (SEC) to take appropriate actions against the accused.

"We are not sure how the house caught fire. It needs to be ascertained whether it was intentional or was caused by a short circuit. The bodies are being sent for autopsy," an officer from Kakdwip police station said.

No one has been detained in the incident.

The polling, for electing 38,616 representatives across three tiers of state (rural) bodies that started at 7 a.m. and would continue till 5 p.m., was marred by sporadic violence and clashes between opposing political groups.