Ankara – Mevlut Altintas, the Turkish policeman who assassinated Russian ambassador Andrei Karlov in Ankara in December, had also researched the whereabouts of the US ambassador to Turkey, according to investigating sources in this matter.

Investigators examining Altintas’s computer have found that just before the murder, he searched for information about US ambassador John Bass.

He also collected information about the activities of Russian and American cultural centers in Ankara, Turkish newspaper Milliyet reported on Thursday.

The findings have led investigators to wonder if Altintas was also planning an attack on the US ambassador.

Russian Ambassador Andrei Karlov was shot dead by Altintas, who was on leave from the police force at the time of the attack, at the opening of an art exhibition on December 19.

Ankara prosecutor’s office asked the US Federal Bureau of Investigation (FBI) for assistance in investigating Karlov’s murder.

Prosecutors want the FBI to help them hack the iPhone used by the 22-year-old killer.

They have also made a written request to Google’s Gmail service, asking them to restore messages that were deleted from Altintas’s email account two hours after the murder.

In response, the email service said that it was not possible to restore the deleted messages.

Investigators therefore sought the FBI to help them access the messages via the server from which they were deleted.

On the other hand, head of the ruling Justice and Development Party (AKP) in Esendere, Tayfun Ayhan, was injured and his brother Murat Ayhan was killed in an armed attack in the Yuksekova district of Hakkari on Thursday.

The two brothers were attacked in front of their home in the Yenimahalle neighborhood by unidentified parties after returning from a campaign for an April 16 referendum on an executive presidency in Turkey.

Following the attack, security forces launched an operation in the Yuksekova city center to catch the perpetrators.