Calcutta, July 18: The body was hidden at a vacant construction site. The cops suspect strangulation or bludgeoning, and have started a case against "unknown persons".

The lone witness can't speak, so everything hinges on the autopsy.

The victim was a 10-month-old. A cat.

"One" - as owner Saikat Sarkar had named it - vanished from its Patuli home last Sunday. Last night's discovery of its carcass has led to a police case under the Prevention of Cruelty to Animals Act and Section 429 of the IPC (mischief by killing or maiming of animals), which carries up to five years' jail.

The Sarkars have 15 more cats. "One and Ladykenny disappeared on July 12. Ladykenny returned last night, alone. It was behaving abnormally and appeared restless while crossing the under-construction building adjoining our home," said Sarkar, 33, who said he ran an online marketing and management firm.

A torchlight search revealed the body "on the floor, covered by a sack whose corners had been pinned down with bricks," Saikat said.

He and wife Sudipa alleged their cats had been under constant attack from the labourers at the site since Saikat had accosted them over broken windowpanes six weeks ago.

"Recently, we found one of our cats, Keltu, inside a gunny bag and hidden under a pile of bamboo sticks, with just its head sticking out," Sudipa said. "The labourers denied everything."

The labourers are on holiday and will be questioned once they return, said an officer at Patuli police station. He explained the possible line of investigation.

"The post-mortem (at the veterinary university in Belgachhia) will pinpoint the cause of death," he said, "and the time, which can be matched against the start of the labourers' holiday. But pinning blame will be a challenge."

Two years ago, a man was arrested under similar sections for killing a stray cat in Bhowanipore and is on trial. But eyewitnesses had made the police's job easy.

"A witness would've helped," the Patuli officer said. If only Ladykenny could speak.