By Asit Jolly
BBC News, Chandigarh
The police say the rats have had been very successful in scaring away pests
Police in India's Haryana state believe they have found a novel way to tackle a plague of mice infesting official records and destroying evidence.
They have started using a pair of domesticated white rats to scare the mice away.
Rodents are a huge problem in India, consuming tonnes of grain intended for human consumption every year.
The experiment has now attracted the attention of animal experts, who think it could be a solution to the problem.
Armies of mice
Despite all the modern weapons available to them, the police in Haryana had until now failed to combat the population of rodents feeding their way through official documents and other critical evidence.
The situation was particularly bad in the central district of Karnal, where armies of mice have, over the years, destroyed many court records.
"Innumerable rodents have invaded the Moharar Maalkhana [record room] and we have been helpless," said the senior superintendent of Karnal, Arshinder Singh Chawla.
"These rats or mice are voracious eaters and have chewed up vital papers, clothing and even the jute [rough fibre] sacks we normally use to store narcotics, illicit alcohol and weapons confiscated from criminals and crime scenes," he said.
The rodents seem to be especially fond of jute bags laced with the intoxicating flavour of bhukki, or poppy husk - a commonly-used narcotic in Haryana which is seized in large quantities from drug peddlers, said Mr Chawla.
But now, Mr Chawla and his men seem to have found an unlikely solution to their problem in a pair of albino relatives of the pest rodents.
"About a month ago, a man from Ambala [a nearby town] suggested that we use domesticated white rats," the officer said.
Rodents eat their way through tonnes of food in India every year
Willing to try just about anything, the Karnal police purchased two white rats from a laboratory animals supplier for 200 rupees ($4; £3).
"It is working like magic," he said.
"My men have been releasing them in the Maalkhana every night and the pests have just disappeared.
"And the best part is that our guards don't touch the documents or the poppy husk, we keep them well fed on a diet of fresh milk and roti," said Mr Chawla.
The unusual experiment in the police compound at Karnal has attracted the attention of university animal biologists. Mr Chawla has already had a number of queries from the small animals lab of the Haryana Agriculture University at Hissar.
Rodents are a huge problem in the northern states of Haryana and Punjab, the leading wheat and rice producing areas of India.
Officials say tonnes of food grain are lost to rats and mice every year, while field rats often weaken canal banks by building burrows, leaving farmland and village populations prone to floods.
Operations to remove landmines laid along the Indian-Pakistan border in 2002 became increasingly precarious after it was discovered that rats had moved hundreds of anti-personnel mines from their mapped locations.
The government and private organisations - including India's railways, which transports the majority of the country's grain supplies - spend millions every year trying to control the rat menace.
Mr Chawla said he had no clue why or how his pet white rats were doing the job, but it could be that he has discovered a new way of tackling India's rodent problem.