A landmine exploded on Monday at Lalgarh in West Midnapore district on the second day of the three-day bandh called by the People's Committee against Police Atrocities.
The landmine went off in a jungle at Bankisole village in the restive area when the security forces were on a routine patrol. However, no one was injured in the blast, police said.
A gun battle was also reported between the Maoists and the security forces from the area in the morning, official sources said.
Wanted PCAPA chief Chhatradhar Mahato had called the bandh to protest against "police atrocities on innocent people" for the past few months.
Transport services were affected in many areas due to the bandh.
According to sources, many CPI-(M) local committee and panchayat members in Lalgrah, Ramgarh, Manikpara, Belpharai and Goaltore have quit their party allegedly under pressure from the Maoists.