The incident occurred when the girls had gone into deep waters to take bath.
They actually had gone to the river to bring clay to make ovens for Chhath puja, Sub-Divisional Police Officer Mohammad Shaifur Rahman said.
The bodies of all the victims have been fished out.
They deceased were identified as Juhi Kumari (11) and Archana Kumari, Kajal Kumari, Sanjana Kumari, all aged 12 years. They were residents of Taajnipur village, the SDPO said.