NEW DELHI, India (AFP) — Indian authorities were engaged in a major search and rescue operation Monday to find 39 people missing after their tour boat capsized in a fast-flowing swollen river.

Police told AFP that eight bodies have been recovered, down from a previous tally of 12, after the accident on the Godavari river in the southern state of Andhra Pradesh on Sunday.

The boat was carrying a total of 73 passengers, of whom 26 have been rescued, local police official Adnan Asmi said.

Almost 300 personnel using boats and a helicopter were engaged in the search operation on Monday including from the Indian Navy and the National Disaster Response Force.

Media reports said that a special diver team equipped with sonar equipment was expected to reach the spot later in the day from the northern state of Uttarakhand.

The vessel was heading to a popular picnic spot when it capsized. Local media reports said the Godavari river has been in spate for a week.

A report in the Times of India quoted a senior Andhra Pradesh minister as saying that the vessel had no licence or permission to carry tourists while the river was swollen.

Poor safety checks and overcrowding are major causes of boat tragedies in India, especially during the current monsoon season.

Indian Prime Minister Narendra Modi expressed his condolences.