Four people are in custody after 50 people were killed and 20 more were seriously injured in shootings at two mosques in the New Zealand city of Christchurch.
New Zealand Police said there had been "multiple fatalities" following what they described as a "tragic series of events" in the Canterbury region on Friday.
What has happened in Christchurch?
Officers first responded to reports of shots fired in central Christchurch at about 1.40pm local time (12.40am GMT).
Two shootings took place at two separate mosques in the city, one at Masjid Al Noor mosque on Deans Avenue and another at Masjid Mosque, Linwood Avenue.
Police said they also defused a number of improvised explosive devices found on vehicles after the shootings.
All schools and council buildings were put on lockdown and members of the public were told not to go outside. The lockdown has since been lifted.
Attack 'streamed live'
New Zealand police have warned that "extremely distressing footage" exists relating to the shooting in Christchurch and have urged that it not be shared.
A video reportedly streamed live on Facebook showed a gunman filming himself firing at worshipers inside the Al Noor mosque.
Facebook later said they had removed the video and disabled the account.
Four people were taken into police custody following the attack. A white male dressed in camouflage, army-style clothing who identified himself as Brenton Tarrant filmed himself opening fire in the Al Noor mosque.
Twenty-eight-year-old Australian Brenton Harrison Tarrant appeared in court on Saturday charged with murder over the attack. Police said more charges would follow.
Wearing handcuffs and a white prison shirt, the Australian-born former fitness instructor and self-professed fascist sat impassively as the judge read the charge against him.
He did not request bail and was taken into custody until his next court appearance scheduled for April 5.
Jacinda Ardern said: "This individual has travelled around the world with sporadic periods of time spent in New Zealand.
"They were not a resident of Christchurch, in fact they were currently based in Dunedin at the time of this event.
"Inquiries are ongoing to establish whether the other two who were arrested were directly involved with this incident.
"The forth person who was arrested yesterday was a member of the public who was in possession of a firearm, but with the intention of assisting police.
"They have since been released."
Tarrant left a 74-page anti-immigrant manifesto in which he explained who he was and his reasoning for his actions. He said he considered it a terrorist attack.
Ms Ardern says the suspect held a Category A gun licence which enabled him to legally obtain semi-automatic weapons. She says the country's gun laws will change in the wake of the attack.
Tarrant said he was of Scottish, Irish and English stock and moved to New Zealand temporarily to plan and train and then stayed there after deciding to conduct the attack.
“I have read the writings of Dylann Roof and many others, but only really took true inspiration from Knight Justiciar Breivik,” he wrote.
Australian Prime Minister Scott Morrison said: "I can confirm that the individual who was taken into custody I have been advised is an Australian-born citizen," he told reporters in Sydney.
"As family members with our New Zealand cousins today, we grieve, we are shocked, we are appalled, we are outraged, and we stand here and condemn absolutely the attack that occurred today by an extremist, right-wing, violent terrorist."
Tarrant appeared in court on Saturday on one count of murder and is remanded until April 5.
New Zealand's Prime Minister has confirmed 49 people dead with another 20 seriously injured in today's attacks.
Several of those killed or wounded in the shooting rampage were from the Middle East or South Asia, according to initial reports from several governments.
Jacinda Ardern said her government was working with consular officials from countries including "Pakistan, Turkey, Saudi Arabia, Bangladesh, Indonesia and Malaysia," to deal with the aftermath of the attack.
The Bangladesh cricket team was arriving for Friday prayers when the shooting occurred but all members were safe, a team coach said.
Thirty-nine people remain in Christchurch Hospital, 11 of them in intensive care.
New Zealand's 'darkest day'
A solemn New Zealand Prime Minister Jacinda Ardern said Friday the deadly mosque shootings in Christchurch had plunged the country into one of its "darkest days".
"Clearly, what has happened here is an extraordinary and unprecedented act of violence," Ardern said in an address to a shocked nation.
"Many of those who will have been directly affected by this shooting may be migrants to New Zealand, they may even be refugees here," Ardern said.
"They have chosen to make New Zealand their home, and it is their home. They are us. The person who has perpetuated this violence against us is not."
"They should have been in a safe environment," she said.
Ardern reiterated her promise that gun laws would change in New Zealand, and said the firearms used in the mosque shootings appear to have been modified.
She said: "New Zealanders will question how someone can come into being in possession of weapons of this nature.
"The guns used in this case appear to have been modified. That's a challenge police have been facing and a challenge we will look to address in changing laws."
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