Turkish authorities have released a CCTV picture of the New Zealand mosque suspected killer after he had an extended stay in the country in 2016.

Australian-born Brenton Tarrant, 28, allegedly livestreamed his sickening attack on two Christchurch mosques on Friday, leaving 49 dead.

Ankara on Friday said it was investigating Tarrant's multiple visits to Turkey, and who he might have met while he was there during an 'extended period of time in the country.'

The Bulgarian government has also said it was looking into Tarrant, who apparently visited the country late last year, as well as Serbia, Croatia, Montenegro and Bosnia and Herzegovina.

Tarrant is said to have set off on a journey around the world in 2011, taking a particular interest in the Balkans and Turkey and the former conflicts between Christians and Muslims.

Turkish authorities say this shows the arrival of Brenton Tarrant, in Istanbul's Ataturk International airport in Turkey on March 2016

Tarrant pictured in North Korea in this undated photo - he travelled across Asia after leaving New Zealand in 2011

A map showing the countries Brenton Tarrant is said to have visited during his seven years of travelling from 2011 to 2018

Along his weapons Tarrant had scrawled names in English and Cyrillic of numerous military figures - many of them Europeans involved in fighting the Ottomans in the 15th and 16th centuries. A few took part in the Crusades, centuries earlier.

In a previous Facebook message about his sojourn in Pakistan on Facebook, Tarrant wrote: 'an incredible place filled with the most earnest, kindhearted and hospitable people in the world,' The Sydney Morning Herald reported.

'The beauty of hunza and nagar valley in autumn cannot be beat,' he stated.

Tarrant claimed in a so-called 'manifesto' to have made money trading Bitcoin, enabling him to travel the world. He is said to have visited a wide range of countries including North Korea, Japan and India.

He visited Bulgaria from November 9 to 15 last year claiming he wanted 'to visit historical sites and study the history of the Balkan country', according to Bulgaria's public prosecutor Sotir Tsatsarov.

Tarrant reportedly went travelling in 2011 after his father's death

Tsatsarov said he hoped the inquiry would establish if this was 'correct or if he had other objectives'.

Turkish border authorities are also examining two trips by Tarrant to the country in 2016, CCTV footage capturing him walking through the airport in March, 2016.

A senior Turkish official says Tarrant spent an 'extended period of time in the country' across multiple trips.

He says the suspect may have also travelled to countries in Europe, Asia, and Africa.

The official says an investigation is underway of 'the suspect's movements and contacts within the country'.

A picture posted on social media by a Pakistani hotel manager in 2018 appears to show him in the country during his time abroad.

But at some point he seems to have become obsessed with terrorist attacks that happened in Europe between 2016 and 2017. His ranting manifesto is filled with Neo-Nazi ideology and hatred for Muslim people.

The alleged terrorist was brought up in rural New South Wales town of Grafton which he left shortly after his father Rodney died of cancer when Tarrant was in his early 20s.

One woman who knew him before he left Grafton speculated to Daily Mail Australia that 'something happened to him' during his time abroad. She also recognised him as being the man in the massacre video.

The alleged Christchurch mosque killer was pictured in Pakistan, as he wrote about the wonderful people who lived there

Another image from Tarrant's social media appears to show him taking photos in the highlands of Pakistan in 2018

She said: 'I know he's been travelling since he left Grafton. He has been travelling overseas, anywhere and everywhere.

'I would say it's something in the nature of his travels, something he's been around.

'I know he's been to lots of different countries trying to experience lots of different things in life and I would say something's happened in that time in his travels,' she said.

In a twisted manifesto that he posted online before the massacre, Tarrant described himself as an 'ordinary, white man', who was born into a working class, low income family of Scottish, Irish and English decent.

Tarrant's father, Rodney, who was a competitive athlete, died of cancer in 2010 aged just 49 and his mother and sister are rumoured to still live in the area.