A British court has sentenced four Sikh extremists to a total of 49 years and six months in prison for carrying out a revenge attack on Lt General Kuldip Singh Brar (retd), who led the 1984 Operation Bluestar.

Dilbag Singh (37) of London and Mandeep Singh Sandhu (34) of Birmingham were sentenced to 14 years each. Harjit Kaur (39), also of London, was sentenced to 11 years, while Barjinder Singh Sangha (34) of Wolverhampton was given 10 years and six months.

Brar and his wife Meena, in London on a private visit, were attacked near their hotel in the heart of the British capital on September 30, 2012. The extremists are understood to have been seeking revenge for Brar’s role in Operation Bluestar carried out 29 years ago to flush out extremists from the Golden Temple.

A key role in the attack was played by Harjit Kaur, who followed the couple by boarding their bus, and reported their movement to the attackers. When Brar and his wife reached Old Quebec Street in the fashionable West End, the male attackers pounced on him and pinned him down as they tried to cut his neck.

He was left with a 12-inch cut to his neck and a three-inch cut to his jaw. Brar’s attackers were found guilty last September of wounding with intent, but sentencing was postponed until early December. Today, the jury of nine men and two women took just one hour to reach their verdict.

During trial, Brar gave evidence via video link from India, saying one website had declared him the "number one enemy of the Sikhs". Another threat received by him read: "There have been seven attempts on his life which have not succeeded, but the eighth one will."

In a statement, the Crown Prosecution Service said, "This was a violent and life-threatening attack carried out by Sikh extremists on the streets of London’s West End. Lieutenant General Brar sustained deep cuts to his face and neck in full view of his wife near their hotel on Old Quebec Street.”

Marie Reid of the Crown Prosecution Service’s Counter Terrorism Division said, "Lieutenant General Brar was targeted in a highly-planned and pre-meditated attack.

Harjit Kaur was instrumental in carrying out reconnaissance of the area and followed the Brars around London.

The couple was set upon in what was a swift, effective and terrifying ambush; Sandhu and Dilbag Singh held Lieutenant General Brar down as Sangha slashed at his neck with a knife.”