Ankara-The Ankara prosecutor’s office, which is investigating Russian Ambassador to Turkey Andrey Karlov’s murder, asked the US Federal Bureau of Investigation (FBI) for assistance in tracing the deleted emails of the murderer, according to a source in law enforcement agencies.

Mevlut Mert Altintas, an off-duty policeman, was killed in a shoot-out with security forces after he shot dead Karlov at a ceremony in an Ankara art gallery on Dec. 19, 2016.

Investigators now hope to retrieve the data in Altintas’s cellphone with the aid of Apple Company in Istanbul as the assassin’s phone and laptop are from the company’s products.

The FBI will provide assistance to Turkish authorities to trace the deleted emails of Altintas. The murderer destroyed all his digital footprints, from his social media accounts to emails, before he donned a suit and sneaked into the art gallery posing as a bodyguard for Karlov. Security forces managed to retrieve part of the deleted data.

In the latest development regarding the murder, a Russian woman allegedly linked to Altintas was arrested by police in Ankara following her detention last month.

The woman had contact over the phone with Altintas. Their phone calls date back to November, 2016.