One more Maoist is suspected to be dead in the ongoing operation by the specialised Thunderbolt squad near Attappadi in Palakkad, police said on Tuesday.
A top police official told that the one who died on Tuesday was injured in the gunfight the previous day, taking the toll to four.
Three Maoists, including a woman, were killed in the operation on Monday.
"It seems like one more member of the insurgents was found dead. We are waiting for the confirmation. But there are also reports of firing at the inquest team members from the forest," the official said.
Opposition Congress on Tuesday alleged in the Assembly that the ruling Left has made it as a policy to eliminate the insurgents instead of bringing them to justice.
With the current operation resulting in the death of four Maoists, the total toll, since the government came to power in 2016, has gone upto seven.
"We are opposing the ideologies of Maoists. But we cannot agree to the fake encounters to kill them," Opposition Leader Ramesh Chennithala told media. He had earlier told the Assembly that during the previous Congress-rule, they had captured two wanted Maoists -- Rupesh and Shina -- instead of killing them in fake encounters.