Brenton Tarrant, the accused Christchurch shooter, makes a white power sign during his court appearance Image Credit: AFP

CHRISTCHURCH, New Zealand: A right-wing extremist who filmed himself on a shooting rampage that left 49 mosque-goers dead flashed a white power gesture as he appeared in a New Zealand court Saturday charged with murder.

Australian-born 28-year-old Brenton Tarrant stood in the dock wearing handcuffs and a white prison smock, as the judge read a single murder charge against him.

A raft of further charges were expected.

New Zealand mosque attack suspect visited Croatia: Police

The Australian extremist suspected of carrying out the New Zealand mosque massacre visited Croatia just over two years ago, police told the Hina news agency on Saturday.

The man believed to be responsible for gunning down 49 people at two mosques in Christchurch on Friday has been identified as 28-year-old Brenton Tarrant.

He was charged in court on Saturday, with investigators now trying to piece together how his extremist views managed to go undetected by the intelligence services.

"The police have information about the movements of this person in December 2016 and January 2017," a spokeswoman for Croatia police said.

Earlier on Saturday, local media said Tarrant had visited Zagreb during that period as well as several other towns on Croatia's Adriatic coast, including Zadar, Sibenik and Dubrovnik.

Croatian investigators are looking into the reasons for his visit, Prime Minister Andrej Plenkovic told HRT national television.

On Friday, Bulgaria also began investigating a recent visit by Tarrant between November 9-15 last year, claiming he wanted "to visit historical sites and study the history of the Balkan country," chief prosecutor Sotir Tsatsarov said.

He had also made a short visit to the Balkans from December 28-30, 2016, travelling by bus across Serbia, Croatia, Montenegro and Bosnia and Herzegovina, they said.

Media reports said the gunman had listened to a Serbian song about convicted war criminal Radovan Karadzic en route to the massacre, and also had the names of two historical Serbian and Montenegro leaders written in Cyrillic on his gun.

Ethnic hatreds fuelled the bloody dissolution of Yugoslavia in the 1990s, sparking wars that left 130,000 dead and displaced millions as borders were redrawn.

Self-professed fascist

The former fitness instructor and self-professed fascist occasionally turned to look at media present in court during the brief hearing that the public were excluded from for security reasons.

Map of Christchurch, New Zealand, showing the two mosques targetted in a gun attack that has left 49 people dead Image Credit: AFP

Flanked by armed police he flashed an upside-down "okay" signal, a symbol used by white power groups across the globe.

He did not request bail and was taken into custody until his next court appearance which is scheduled for April 5.

A still image taken from video circulated on social media, apparently taken by a gunman and posted online live as the attack unfolded, shows him driving in Christchurch, New Zealand.

A short distance away, 39 people were being treated in hospital for gunshot wounds and other injuries inflicted in the massacre. They included a two-year-old boy and a four-year-old girl, who is in critical condition.

Doctors at Christchurch hospital said they worked through the night in 12 operating theatres to do what they could to save the survivors.

Christchurch residents piled bouquets of flowers at a makeshift memorial near the Al Noor mosque, many accompanied with handwritten letters laden with sadness and disbelief Image Credit: AFP

For many, the road to recovery will require multiple surgical procedures and many survivors said the mental scars may never fully heal.

The attack on the Al Noor and Linwood mosques has been labelled terrorism by Prime Minister Jacinda Ardern and is thought to be the deadliest attack directed against Muslims in the West in modern times.

Outside the court, the son of 71-year-old Afghan victim Daoud Nabi demanded justice for his late father, who believed New Zealand to be a "slice of paradise."

"It's outrageous, the feeling is outrageous," he said. "It's beyond imagination."

The attack on the Al Noor and Linwood mosques has been labelled terrorism by Prime Minister Jacinda Ardern Image Credit: AFP

Ardern said the victims came from across the Muslim world, with Turkey, Bangladesh, Indonesia and Malaysia among the countries rendering consular assistance.

One Saudi citizen and two Jordanians were among the dead, while five Pakistani citizens were missing.

Tributes to victims

Tributes to the victims poured in from around the world.

US President Donald Trump condemned the "horrible massacre" in which "innocent people have so senselessly died", but denied that the problem of right-wing extremism was widespread.

As of Saturday morning, 42 people remained hospitalized, and two people, including a 4-year-old child, are in critical condition, New Zealand Police Commissioner Mike Bush was quoted by the Defense Post.

3 people arrested

Prime Minister Jacinda Ardern said three people had been arrested, and inquiries were ongoing as to whether the other two were directly involved.

A fourth person arrested on Friday was a member of the public in possession of a firearm with the intention of assisting police and has been released.

Speaking in Sydney, Australian Prime Minister Scott Morrison described the gunman as "an extremist, right-wing, violent terrorist".

New South Wales police commissioner Mick Fuller said police had visited Tarrant's childhood home in the town of Grafton, north of Sydney, and spoken to family members as part of their investigation.

The attack has prompted searching questions about whether right-wing extremism has been treated with enough seriousness by Western governments.

Terrorist's assault rifle: The New Zealand mosque shooter names his 'idols' on weapons he used in massacre. Image Credit: Daily Sabah

Ali Soufan, a former high-ranking FBI counter-terrorism agent, said the threat needs to be treated with the same seriousness as jihadist violence.

"We are in the midst of a surge of right-wing terrorism that has been metastasising in plain sight while generating only a muted response from domestic counter-terrorism authorities," he said.

Ardern said she would be reviewing events leading up to the attack to see how the suspect went unnoticed by authorities.

"The individual charged with murder had not come to the attention of the intelligence community, nor the police, for extremism," she said.

"I have asked our agencies this morning to work swiftly on assessing whether there was any activity on social media or otherwise, that should have triggered a response. That work is already underway."

FACTBOX: Mass shooting incidents in New Zealand

SYDNEY (Reuters): New Zealand suffered its worst peacetime shooting as at least one gunman, a suspected white supremacist, killed 49 people during Friday prayers at two mosques in Christchurch, the largest city on South Island.

Violent crime is rare in New Zealand and police do not usually carry guns, though mass shootings have occurred previously.

Here is a list of some previous incidents:

1997: A lone shooter killed six people, including his father, and wounded four others in the ski-lodge hamlet of Raurimu. He was tried and found not guilty by reason of insanity.

1994: Seven members of the Bain family were shot dead in Dunedin, South Island's second largest city. A surviving son was convicted of their murders in 1995, but later acquitted at a retrial in 2009 and awarded a payout of almost NZ$1 million ($680,000).

1992: At a farm outside Auckland, Brian Schlaepfer shot and stabbed six members of his own family before killing himself with a shotgun.

1990: A gun-mad loner killed 13 men, women and children in a 24-hour rampage in the tiny seaside village of Aramoana. He was killed by police. It prompted a modest tightening of gun laws.

1943: Forty-eight prisoners-of-war and a guard died when officers opened fire on rioting inmates at a camp holding Japanese soldiers captured during the Guadalcanal Campaign. A court martial determined prisoners were responsible, but no charges were pressed.