The death of Dr Deepak Amrapurkar, a gastroenterologist who worked with Bombay Hospital in Mumbai, had caused widespread outrage.
Dadar police in central Mumbai on Sunday arrested Siddhesh Bhelsekar, Rakesh Kadam, Nilesh Kadam and Dinesh Pawar, residents of a chawl in Parel area.
Probe found that they had opened the manhole so that the water in the area, which had entered their houses, could drain out, police said.
Dr Amrapurkar went missing after getting out of his car which was stuck in a traffic jam and walking home along a waterlogged street near the Elphinston Road station on August 29, when torrential rains brought the city to a halt.
Eye-witnesses said that they saw a man falling into a manhole while wading through water. Amrapurkar's body was recovered after two days from a nullah in central Mumbai's Worli area.
The four accused have been booked under section 304 (A) (causing death by negligence), said an officer from the Dadar police station, adding that further investigation was underway.
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