Though the video was shot in July, almost a month after the death of Bollywood actor Sushant Singh Rajput, the Narcotics Control Bureau (NCB) on Thursday night issued a notice to Karan, seeking an explanation from "the party host".

"Karan Johar is now under the scanner in the ongoing probe into the Bollywood drugs scandal. If needed, he will be summoned for questioning soon," a senior official told the media in Mumbai.

It may be mentioned here that in September when rumours of drug consumption at his home were doing the rounds in Bollywood, Karan had termed the same as "slanderous" and "malicious".

Also read: Bollywood drugs scandal grips India's entertainment industry

"These slanderous and malicious statements, news articles and news clippings have unnecessarily subjected me, my family, and my colleagues, and Dharma Productions, to hatred, contempt and ridicule," he had said in a statement.

NCB sleuths started probing the drugs scandal following the death of Sushant Singh. Among the first to be arrested in connection with the case were his actor-girlfriend Rhea Chakraborty and her brother Showik. Both are currently out on bail.

Also read: Bollywood drugs scandal: Celebrity hairstylist held

Rhea was, in fact, arrested by NCB on September 9, following days of questioning, and accused of procuring cannabis for her late actor-boyfriend, whose body was found hanging from a ceiling fan in his Mumbai flat on June 14.

Immediately after the arrest of Rhea, the names of at least 20 top Bollywood celebrities — from actors to filmmakers to designers — surfaced in the drugs case. Several of them, including leading female Bollywood actors —  Rakul Preet Singh,  Deepika Padukone, Sara Ali Khan and Shraddha Kapoor — were subsequently grilled by NCB.

Also read: Indian sleuths achieve 'major breakthrough' in Bollywood drugs scandal

The grilling came in the wake of WhatsApp chats retrieved from Rhea's mobile phone indicating that they procured banned substances like cannabis, weed and hash from dealers with links to foreign countries. All the actors, however, reportedly denied any links with such drug dealers.