Officials said heat stroke could be a probable reason behind the tiger's death. (FILE PHOTO)

A tiger has died at the Sariska Tiger Reserve in Rajasthan's Alwar district, officials said on Sunday.

The male tiger, aged around seven-eight years, was shifted to Sariska from the Ranthambhore National Park, in Sawai Madhopur, only two months ago.

An autopsy was conducted on Sunday in the presence of experts, they said.

"The exact cause of the death will be clear after pathological examination of samples collected during post-mortem but prima facie, heat stroke could be a probable reason," Chief Wildlife Warden Arindam Tomar said.

The tiger had sustained some injuries when he was freed from enclosure, Mr Tomar said.

He was tranquillised on Saturday, after which he walked for nearly two kilometres and collapsed, the wildlife warden added.

"Postmortem was conducted today as per the protocol, and other experts were also present so that full transparency is maintained," Mr Tomar said.

The Sariska Tiger Reserve is now left with three tigers, eight tigresses and five tiger cubs.