Ram Bahadur Kurumbang, chief district officer of Pyuthan district, said the Indians were identified as Suresh Kumar Sahu, 16, Gop Raj Gupta, 70, Saraswoti Sahani, 62, Suresh Sau, 15, Urmila Pandey, 66, Suvadra Yadav, 65, and Pinku Ojha, 24.
At least 17 people were killed on Monday when a jampacked bus swerved off the road and plunged into the Madi river in Gothibang.
On Tuesday, two critically injured people died at a hospital in Bhairahawa, a town on the border with India, while another critically injured man breathed his last at a hospital in Pyuthan.
Phanindra Baral of the Pyuthan district hospital said 56 people were receiving treatment in Bhairahawa while one is undergoing treatment in Pyuthan.
Kurumbang said the bodies of nine men and seven women were sent to Bhairahawa after post mortem examination.
The bus met with the accident while it was heading to Krishnanagar of Kapilvastu from Bhingri in Pyuthan.
Most of the passengers were Indian pilgrims returning from the Swargadwari Temple in west Nepal, a popular pilgrimage site for Hindus.
Meanwhile, the Indian embassy sent a team to the accident site to coordinate with the local authorities in the rescue operation, the embassy in Kathmandu said in a statement.
"A joint rescue team of Armed Police Force, Nepal Army and Nepal Police have been carrying out rescue operations at the accident site," the embassy said.
Syed Akbaruddin, spokesperson for India's external affairs ministry in New Delhi, said in a tweet Tuesday: "India's mission coordinating arrangements at Bhairahawa in Nepal to ensure all assistance to relatives of pilgrims killed in bus accident."