Shweta Singh Kirti, sister of late actor Sushant Singh Rajput, has called the alleged drug chat of Rhea Chakraborty a criminal offence and wants action to be taken against the actress.Shweta took to Twitter on Wednesday and asked the CBI to take action against Rhea."This is a CRIMINAL OFFENSE!! An immediate action should be taken by CBI on this. #RheaDrugsChat," wrote Shweta on her unverified Twitter account. She also shared the clip of a news report that declared: "Sushant was administered something without his knowledge. That ultimately led to his death: Sushant Singh's family lawyer".Meanwhile, Rhea's lawyer said on Tuesday that the actress has never ever consumed drugs and is ready for any test.Sushant was found dead at his flat in Mumbai's Bandra on June 14. His girlfriend Rhea and her family has been accused by the late actor's father of abetting his son's suicide, among other charges.