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The Communist Party of India, meanwhile, has condemned the killings and called for an independent inquiry.Last month, the Indian government launched a massive military operation - known as Black Forest - targeting the group.

Shah said on Wednesday that 54 rebels had been arrested so far, and 84 had surrendered in the states of Chhattisgarh, Telangana, and Maharashtra, as a result.The operation was launched after the Maoists said they were ready for talks with the government if it halted its offensive and withdrew its troops. Chhattisgarh officials said any dialogue must be unconditional.The Maoists are inspired by the Chinese revolutionary leader Mao Zedong. Their insurgency began in West Bengal state in the late 1960s and has since spread to more than a third of India's 600 districts.

The rebels control large areas of several states in a "red corridor" stretching from north-east to central India.Major military and police offensives in recent years have pushed the rebels back to their forest strongholds and levels of violence have fallen.

But clashes between security forces and rebels are still common, killing scores of people every year.

A crackdown by security forces killed around 287 rebels last year - the vast majority in Chhattisgarh - according to government data. More than 10,000 people are believed to have died since the 1960s.But a former senior General told the BBC that in a real war it would run out of ammunition, spares and supplies within weeks or even days. Nor does Britain have much in terms of ground-based air defences – not enough to protect key military bases in the UK, yet alone its towns and cities.

The weaknesses in Britain's contribution to Nato became starkly apparent in February this year, when a group of British MPs visited a Nato military site in Tapa, Estonia, where British soldiers are deployed (alongside Danish and French troops). The point of the base is to deter or slow down an invasion from Russia - which is just 80 miles away over a land border.Mike Martin, a Liberal Democrat MP and former British Army Officer, said the Estonia visit was like going back in time, seeing the same equipment as when he first joined the Army as a reservist in 2004: ageing Challenger 2 tanks and Warrior armoured vehicles. What one former General described to me as "legacy kit from the 1980's" - old and dwindling in numbers.

About 1,000 British troops are stationed at the site. At the time of the MPs' visit they were armed with some drones - though not many. Nor did they have much in the way of systems to block or jam enemy drones, either. They also have a handful of long-range artillery guns - important for land warfare. The British Army currently has a total of just 14. Even tiny Estonia has double that number.Defence sources say that since the MPs' visit, the Army has now begun to test some of the new technology it wants to introduce. They say it "will help soldiers see further, and strike faster".