A day before the start of the monsoon session of Parliament, Bikaner police on Monday arrested one person, allegedly kingpin of Congress president Sonia Gandhi's son-in-law Robert Vadra's dubious land deals in Rajasthan. The man, identified as Jay Prakash Bangarwa, is a resident of JNV Colony, in Bikaner. He was chairman of Loonkaransar Krishi Mandi from 2006 to 2011. The headway into Vadra land deals could come handy for the BJP.