The NCB questioned Deepika for over five hours on Saturday and Rakul for over four hours on Friday.
Meanwhile, Karishma was questioned for two consecutive days on Friday amd Saturday, while Khambatta was grilled on Friday.
The agency collected their phones as the alleged 'drug' chats were made using the same phones, the source said.
The source also said that the NCB has collected the phone of Sushant's former talent manager Jaya Saha.
Besides Deepika, Rakul, Khambatta and Karishma, the NCB also questioned Bollywood actors Shraddha Kapoor and Sara Ali Khan on Saturday for several hours.
The NCB has registered a case on the request of the Enforcement Directorate (ED) after it found alleged chats of Deepika with her former manager in 2017 discussing drugs.
The phones of Rakul and Khambatta were seized as both of them are close friends of Sushant's girlfriend Rhea Chakraborty, who was arrested earlier this month after three days of questioning.
Besides Rhea, the NCB has also arrested her brother Showik and 17 others in connection with the case.
(Only the headline and picture of this report may have been reworked by the Business Standard staff; the rest of the content is auto-generated from a syndicated feed.)
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