Senior Bihar Police officer Vinay Tiwari, who arrived in Mumbai on Sunday to assist the state police team probing the death of Bollywood actor Sushant Singh Rajput, denied any lack of coordination between the two police forces.

Asked by the reporters at Mumbai airport if he was deputed due to reports of lack of co-ordination between Mumbai and Bihar Police, he said: "It's (his visit) a part of the process of the investigation".

"It can't be said that there is a lack of co-ordination. There is a step called supervision in any process of investigation and for that, a senior officer needs to step in. We are moving in the right direction," Tiwari, an IPS officer of 2015 batch, said.

"I have come here so that I can interact with my team and take the investigation ahead," he said.

Bihar's DGP Gupteshwar Pandey told IANS on Sunday that Tiwari, currently the SP, City, Patna, has been sent to Mumbai to help the four-member Bihar Police team in Mumbai that complained of lack of co-operation by the Mumbai Police over the investigation.

Tiwari also said that his arrival in Mumbai should not be seen as a step by the Bihar Police to arrest Rhea Chakraborty -- Sushant's girlfriend and Bollywood actor, who along with her family members, had been named in a July 25 FIR filed by the late actor's father K.K. Singh.

The Bihar Police are also yet to retrieve any medico-legal document in the Sushant Singh Rajput case.

On this, Tiwari said: "That is why I have come and we will try our best to get all the documents."

On its own part, the Mumbai Police have questioned many people, including filmmakers.

Tiwari, on being asked if his team will also quiz the filmmakers, said: "So far, we are questioning those involved in this case... who were close to him (Sushant) in the last few days (before his death).

"Our team has done a lot of work in this direction. If there is a need to interrogate the filmmakers to carry forward the investigation, we will do that too," he said.

Sushant was found hanging at his Bandra apartment in Mumbai on June 14 following which Mumbai Police began probing the case.

K.K. Singh on July 25 had filed an FIR against his son's star girlfriend Rhea Chakraborty and her family members for allegedly abetting his suicide. Following this, the Bihar Police also launched its investigation.

Bihar's DGP Pandey had told reporters on Saturday that Bihar Police would reveal all facts associated with the matter.

Rhea is presently absconding. The Bihar Police team had also visited her flat but could not find her there. After this, Pandey admitted that the Bihar Police have not been able to 'locate' her.

With Rhea having released a video in which she claimed her innocence, the DGP said that instead of declaring herself innocent on video, she should record her statement before the police, as this will be in her favour.

"Rhea must clear her side. We do not have any enmity with her, but if she continues to run in this way, then it will be difficult for her. I assure you that the Bihar Police are investigating at their own level and the day we get the evidence against the culprits, we will drag them out even from hell. The Bihar Police are fully capable of this task," he asserted.