Several people belonging to the Sikh community gathered outside the British High Commission in Chanakyapuri here on Monday to protest pro-Khalistan separatists pulling down the Indian flag at the Indian High Commission in London a day earlier.

Carrying the tricolour and placards, protesters raised the slogan "Bharat humara swabhiman hai (India is our pride)" and said that they will not tolerate any insult to the national flag.

The tricolour flying atop the Indian High Commission in London was grabbed at by a group of protesters waving separatist Khalistani flags and chanting pro-Khalistani slogans on Sunday, leading to an arrest related to the violent disorder.

Officials from the mission said the "attempted but failed" attack had been foiled and that the tricolour was now flying "grander". The Metropolitan Police said two members of security staff sustained minor injuries which did not require hospital treatment. An investigation has been launched.

India on Sunday night summoned the British deputy high commissioner and demanded an explanation over the complete "absence of security". In a strongly-worded statement, the Ministry of External Affairs said India finds "unacceptable" the indifference of the UK government to the security of Indian diplomatic premises and personnel in the UK.

The UK government will take the security of the Indian High Commission here "seriously", top British officials have said as they condemned as "disgraceful" and "completely unacceptable" the vandalism at the mission.

The banned terrorist organisation, Sikhs For Justice, is conducting a so-called "Referendum 2020" amid a crackdown on pro-Khalistan leader Amritpal Singh in Punjab.

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