Another prominent Hindu leader helping the Conservatives is Trupti Patel, president of the Hindu Forum of Britain. I’ve been sent a recent video of her, clearly at a Hindu event, telling the audience she would ban Labour politicians from Hindu functions, starting with a Diwali event she was to host in Parliament (see above). Labour MPs who didn’t want to be named have confirmed that their invitations to this event had been withdrawn. That appears to fit in with Patel’s broader political leanings: from her personal Twitter account she has approvingly retweeted Katie Hopkins and praised Donald Trump.

Patel is also the chair of Hindu Forum of Britain Charity. However, there is also a limited company listed at Companies House with the similar name of Hindu Forum Britain, with Patel listed as a director. She told openDemocracy: "The HFB is a Company Limited by Guarantee. As president I speak in this capacity."

On 10 October, the National Council of Hindu Temples (UK) and the Hindu Forum of Britain wrote an absurd letter about Kashmir to Corbyn claiming that Labour had become “anti-Hindu” and accused him of trying to “appease the Pakistani vote bank”, and therefore “becoming direct supporters of Islamist terror organisations such as Al-Qaeda and ISIS”.

Both groups are close to Bob Blackman, the Tory candidate seeking re-election as an MP in Harrow East. London Hindus like to joke that he hangs out at their temples more than they do. At a meeting of Conservative Friends of India earlier this year, a source told me Blackman urged the Tories to work more closely with the BJP to defeat Labour. I was told that some audience members raised their eyebrows at that comment.

Hindu organisations across the country are now under pressure to withdraw invitations to Labour politicians so they won’t have a chance even to explain themselves.

Many of the messages on Hindu social media are misleading. For example, it is not only Labour politicians who have raised concerns over events in Kashmir. Conservative MPs Steve Baker and Dan Poulter have done so too, along with Scottish National Party MPs. Even Boris Johnson said at a mosque visit this week: “I have deep sympathies with the people of Kashmir and what is happening there.”

Some of the images circulated on social media have been doctored, like one of Corbyn doing a Hitler salute. Some messages falsely claim Khan boycotted Diwali celebrations. One complaint against Labour MP and Sikh Tan Dhesi was, “He is always seen with Pakistanis and goes to the Pakistan High Commission.” Dhesi has told me he’s never been to the Pakistani High Commission. The list is endless.

The impact on British Hindus has been devastating. I have dozens of messages from community members saying this campaign has caused arguments among families and friends.

One told me: “I got a WhatsApp message [criticising Corbyn] from a relative with the same message being read out at that mandir [temple]. Made it very clear that I will never support the BJP, totally disagree with their actions in Kashmir and would never vote for the Tories. I don’t wonder who has started this propaganda.”

Another wrote: “I'm a London born Hindu Gujju [Gujarati], who believes in the [Bhagavad] Gita and therefore most definitely does not support Modi or the BJP. Just needed to say that so you know that not all people identifying themselves as hindu gujjus are self serving socially irresponsible hypocrites. Take care and thank you for speaking up.”

British Hindus told me that arguments over this campaign have led to bad blood and deep frustration. Many have left family groups over it. Others have been dismayed by what relatives are sharing. “All that was left was for you to tell me how I should follow my faith,” one wrote on a WhatsApp group I’m part of.

The implication that ‘true Hindus’ should support only the BJP is alarming – it implies a religious duty to support the party and anything it does. A majority of Indians in fact voted against BJP candidates in this year’s Indian elections; the party retained power through local alliances.

The BJP wants to establish a Hindu rashtra in India – a country where Hindus are put first. That is neither democratic nor secular. That is a theocracy like Iran or Pakistan. To claim that opposing the BJP’s actions is anti-Hindu is deeply dangerous and alarming.

I’ve seen this kind of campaigning and polarisation before, among British Sikhs and Muslims. There have always been British Sikh and Muslim groups with similar demands: you either support what we say or you are going against your religion and community. It always ends in polarisation, anger and arguments.

The real impact will be felt in years to come. This pro-BJP campaign to browbeat Hindus to vote Tory may not have much electoral impact for now, but it will divide families and communities for a long time. The instigators think it is a price worth paying. But I doubt most British Hindus will think the arguments will be worth it.

We contacted Overseas Friends of BJP UK and Bob Blackman for comment, but they had not responded at the time of publishing.