Those inside the car fired at the police vehicle, which was retaliated in self-defence, officials said.
A cattle smuggler was killed in a gunfight with the police in Assam's Dhubri district, officials said on Sunday.
Acting on a tip-off, police tried to intercept a vehicle in Sapatgram area on Saturday night, they said.
"The car was signalled to stop, but it sped away. Our team started chasing it," a police officer said.
Those inside the car fired at the police vehicle, which was retaliated in self-defence, he said.
"There were three people in the vehicle. One of them died on the way to a hospital, while the other one is undergoing treatment now," he said.
One of the suspects managed to escape, the officer added.
In another incident, a suspected dacoit was injured in police firing in Doboka in Nagaon district, officials said.
The suspect was arrested on Saturday, after which he was taken to recover hidden arms at night, they said.
"He pushed away a constable and tried to run. We had to fire to ensure that he doesn't escape. He was wounded on the right leg," a police officer said.
Altogether 43 people have been killed and at least 107 injured in police action since Chief Minister Himanta Biswa Sarma assumed office in May 2021.