A leading human rights group in southern India is calling for an inquiry into the killing of the country's most notorious bandit.
Exact circumstances of Veerappan's death remain unknown
Police in the state of Tamil Nadu said they killed Veerappan in a well-planned operation after he refused to surrender and opened fire on them.
Veerappan, India's most wanted man, had been on the run for some 20 years.
He was accused of a range of crimes, including more than 100 murders, kidnapping and smuggling.
Tamil Nadu police say the killing of Veerappan and three associates was the result of months of planning.
But the killing could have been avoided, according to the human rights group, People's Watch.
Its head, Henry Tiphagne, asked in an interview with the BBC Tamil Service: "Why could the 100 armed police officers who surrounded Veerappan not have forced him to surrender or simply wounded him?"
Veerappan had many times told journalists how he had bribed police and politicians, and had made clear he would give details if he was ever tried.
Mr Tiphagne said, with Veerappan's death, the allegations of his links to leading figures in Tamil Nadu and Karnataka could not be examined.
The Indian government had offered a 50m rupee ($1.1m) reward for any information leading to Veerappan's arrest.
Tamil Nadu's Chief Minister, Jayalalitha, congratulated police for what she called the "daring operation in which the notorious bandit was killed" on Monday night.
And in neighbouring Karnataka, where the bandit was also based, the government announced free houses for the police officers involved in Veerappan's shooting.
One of Veerappan's most famous victims, leading south Indian actor Rajkumar, said he was happy and relieved to see the end of the bandit who held him and three others hostage four years ago.
"Anti-social elements like Veerappan should not be allowed to live," Rajkumar said.
But some of the hundreds of people who gathered outside the hospital in Dharmapuri where a post-mortem examination was being conducted on Tuesday, said police should have arrested Veerappan and brought him to justice.
The chief of the Special Task Force (STF) - the team specially assigned to catch Veerappan - said the bandit was desperately looking for men to join his dwindling gang.
Vijay Kumar said four undercover STF policemen had been sent to develop a rapport with Veerappan and later managed to gain the bandit's confidence.
Veerappan's ambulance was riddled with bullets
Shortly before his death, Veerappan told them he needed urgent medical treatment as he was suffering from asthma, Mr Kumar said.
He said the STF then laid a trap - an ambulance driven by an undercover policeman was sent to the bandit, while police lay in wait.
When the vehicle reached a marked spot, Veerappan was surrounded and ordered to surrender.
The bandit refused and instead opened fire on the STF men, prompting the retaliatory police fire, Mr Kumar said.
"This was indeed a difficult mission because he was a worthy foe. It was not very easy to get him. This operation was coming at the end of a long wait, a desperate wait," Mr Kumar was quoted as saying by Reuters news agency.