Two rounds of clashes between the two parties took place since morning at Kharkushma village under in Garbeta as CPI(M) supporters were reopening their party office after nine months, police said.
Trinamool Congress activists tried to prevent them from doing so and in the exchange of gun fire, a woman, Chhaya Hazra (50), who was passing by was injured in the foot by a stray bullet, police said.
She had been admitted to Midnapur medical College Hospital, sources said.