The Narcotics Control Bureau (NCB) on Sunday summoned late Bollywood actor Sushant Singh Rajput's girlfriend Rhea Chakraborty for questioning in connection with the drug case.

The NCB officials arrived at the Primrose apartment here to summon Rhea for questioning.

Rhea will join the investigation at around 11 a.m.

The summon to Rhea comes a day after a court on Saturday sent her brother Showik and Sushant's house manager Samuel Miranda to four days NCB custody till September 9.

The NCB arrested Showik and Miranda on Friday night after 10-hour long questioning.

During questioning the NCB got the evidence against the duo and later they were arrested.

On Friday, the NCB also carried out searches at the residences of Showik and Miranda.

The NCB on Saturday also arrested Dipesh Sawant, the personal staff of Sushant.

The NCB had registered a case on August 26 under various sections of the Narcotic Drugs and Psychotropic Substances Act, naming Rhea, her brother, talent manager Jaya Saha, Sushant's co-manager Shruti Modi, and Goa-based hotelier Gaurav Arya, after the Enforcement Directorate wrote to it about the drugs angle.

This followed the discovery of WhatsApp messages between Rhea and Shruti Modi, Miranada and Sushant's flatmate Siddharth Pithani.

The NCB is the third Central agency to join the probe into the death case of Sushant after the Central Bureau of Investigation (CBI) and the ED.