It was last May that Mayur Dangar, a veterinarian at Bai Sakarbai Dinshaw Petit Hospital for Animals in Parel was contacted about a possible spy pigeon idling at Pir Pau pier, a dock at Mumbai Port Trust which chiefly handles oil vessels.

The black-grey pigeon, which was first spotted by the Central Industrial Security Force (CISF), had rings on each of its feet and what appeared to be Chinese markings on its feathers.

Immediately suspicious, the CISF took it to the RCF police station in Chembur, which sent the bird to the city's biggest veterinary hospital Bai Sakarbai Dinshaw Petit Hospital for Animals in Parel.

Thus began what was the most confounding cases he had ever handled, Dangar told ThePrint.

On 29 January, following repeated reminders from hospital authorities, the jailbird was finally set free. This was over two months after authorities found out that what they thought was a Chinese spy was, in fact, a Taiwanese racing pigeon that found its way to India, police said. By the time it was released, it had been held captive for eight months.

When contacted, Ravindra Patil, an assistant police inspector at the RCF police station in Mumbai's Chembur, who was heading the investigation, said there was some "miscommunication".

Until this pigeon case came to him, Ravindra Patil had dealt with only two cases involving animals, both involving dogs. After the bird was taken to the hospital, the rings on its feet were removed and sent to to Forensic Sciences Laboratory (FSL). According to Patil, one of the rings had a microchip, which investigators then traced back to Taiwan.

Investigators were also trying to get an expert to decipher the script on its feathers, but since the bird had flown overseas, the writing had faded. "Nothing more was there on the chip and we even cross-verified the information.

Authorities at hospital, meanwhile, were getting worried. Although the investigation had officially been closed, they received no word from the police.

In January, Mumbai Police finally got back to them saying the investigation had been closed, the veterinarian said.