RK Singh who took oath today, joined BJP before 2014 national election and contested and won in Bihar

Highlights RK Singh, then an IAS officer, arrested LK Advani in 1990 in Bihar

A 1975-batch officer of Bihar cadre, he was Home Secretary under UPA

He joined BJP before 2014 polls; contested and won from Arrah in Bihar

26 years ago, when BJP leader LK Advani's rath rolled into Bihar, then Chief Minister Lalu Yadav ordered his arrest. He chose two officers to stop Mr Advani's rath yatra from Somnath in Gujarat to Ayodhya in Uttar Pradesh. One of them, Raj Kumar Singh, took oath today to join Prime Minister Narendra Modi's council of ministers.In October 1990, RK Singh was an IAS officer serving as a Secretary in the Bihar government. He was flown in a state government chopper early in the morning from capital Patna to Samastipur along with IPS officer Rameshwar Oraon. It Was RK Singh who knocked on the door of the Circuit House where Mr Advani was staying and told the top BJP leader that he had a warrant for his arrest.Mr Singh and Mr Oraon then flew Mr Advani to Patna and from there to the Masanjor guest house in Dumka district of what is now a separate Jharkhand state.Mr Advani's rath yatra to demand a Ram temple in Ayodhya would change the BJP's political trajectory. Within six years of Mr Advani's arrest in Bihar, the BJP first came to power at the Centre and LK Advani served as the country's Home Minister and deputy Prime Minister.Years later Raj Kumar Singh, 64, a 1975-batch officer of the Bihar cadre, would go on to become the union home secretary when the Congress-led UPA was in power at the Centre, cracking down hard on terror and naxalism.

He joined the BJP before the 2014 national election and contested and won from Arrah in Bihar.LK Adavni, 89, who led a group within the party that opposed PM Modi's elevation in the BJP, has since been sidelined.