The son of a Rajasthan legislator who allegedly killed three people by crashing his BMW car into an auto-rickshaw this morning has been arrested in Jaipur, police said. The incident took place around 2 am on today when the speeding white car, allegedly driven by Siddharth Mehria, 20, son of independent legislator from Sikar, Nand Kishore Mehria, collided into the auto-rickshaw first and then a stationary police van.