Delhi Police has registered a case in connection with the protest held outside the Indian High Commission in London on March 19, officials said here on Friday.

The case was registered by the special cell under the Indian Penal Code, Unlawful Activities (Prevention) Act and the Prevention of Damage to Public Property Act as it involves unlawful activities carried out by certain people holding Indian nationality abroad, a senior police officer said.

It was done after the Ministry of Home Affairs directed the Delhi Police to take appropriate legal action on the receipt of a report from the Ministry of External Affairs over the incident at the Indian High Commission March 19.

Last Sunday, 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, 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 last 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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