Stepping up pressure on the UPA over Coalgate, the BJP on Tuesday sought a SIT probe into the whole scam and resignation of Coal Minister Sriprakash Jaiswal for doling out favours to his associates. The party also demanded investigation into fresh revelations that NTPC awarded a coal mine contract worth over `23,000 crore to a joint venture company in which 10 per cent shares were held by the family of former Coal Minister Santosh Bagrodia.