Fifty people have been killed and another 50 wounded in shootings at two mosques in Christchurch, New Zealand, in the deadliest attack in the country's history.
New Zealand Prime Minister Jacinda Ardern called it one of New Zealand's "darkest days".
Here's what we know so far about how the attacks unfolded.
The first shooting took place at the Al Noor mosque, in central Christchurch, on Friday.
A gunman using the name Brenton Tarrant live-streamed footage of his rampage to Facebook, filmed with a head-mounted camera.
Footage showed the man, armed with semi-automatic weapons, firing indiscriminately at men, women and children from close range inside the mosque.
The attacker's headcam footage begins in an industrial estate on Leslie Hills Drive, just west of Al Noor mosque.
It shows him driving south on to Mandeville Street and Blenheim Road towards the city centre before turning north up Deans Avenue.
He reaches the mosque a few minutes later, pulling the car into an alleyway at the side of the building and turning the car around to park facing Deans Avenue.
The suspect then gets out, selects a weapon from the boot of the car and walks to the building, where he begins his deadly attack on worshippers inside.
This was approximately 13:40 local time (00:40 GMT).
Six minutes later, he drives along Deans Avenue, around the Botanic Gardens to Bealey Avenue, where his headcam footage cuts out.
The second attack then took place a little later, five kilometres away at Linwood Mosque, east of the city centre.
Attack 1: Al Noor mosque, 42 dead
Officers responded to reports of shots fired at the mosque during Friday prayers at about 13:40.
By 14:11 police confirmed they were attending an "evolving situation" and schools went into lockdown a few minutes later.
At 14:30 police confirmed the incident involved a gunman.
The headcam images show the gunman passing from room to room, killing as he goes and shooting the wounded from close range.
The attacker targeted both the men's and women's prayer rooms.
"There were bodies all over," one man said.
Attack 2: Linwood mosque, eight killed (one of whom died in hospital later from injuries)
There were fewer details about the attack in the Christchurch suburb of Linwood, where about 100 people were attending prayers at the Linwood Islamic Centre.
At about 13:55, the gunman stepped out of his car and shot a man and his wife, according to local media reports.
Mohammed Akheel Uddin, who had been on car park duty, said he saw the gunman approach the side of the building opposite to the main entrance. Finding no door, the gunman shot at the windows, Mr Uddin told Stuff news website.
He said this gave people inside a chance to get away from the main entrance and hide.
Abdul Aziz, 48, was attending Friday prayers with his family inside the centre when he heard the gunshots. He grabbed a credit card reader to use as a weapon and ran outside, throwing the reader at the attacker as he moved back to his car.
The gunman fired several times at Mr Aziz, who said he was screaming at the man to draw attention away from the mosque.
"I didn't want him to go inside," he said.
Mr Aziz picked up an empty shotgun that the suspect had dropped and followed the attacker back towards the mosque, where he confronted him again.
"When he saw me with the shotgun, he dropped the gun and ran away toward his car. I chased him," he told Reuters news agency. "He sat in his car and... I threw [the gun] through his window like an arrow. He just swore at me and took off."
Mr Aziz said he didn't consider himself a hero - he just did what anyone would have done.
Two police officers, one of them armed with only a handgun, chased and arrested the suspect - 21 minutes after the first emergency 111 call reporting the attack on Al Noor mosque.
Police Commissioner Mike Bush described the twin attacks as a "very well-planned event". Firearms were recovered from both scenes.
Two IEDs (improvised explosive devices) were found in a car and neutralised by the military, police said.
Australian national Brenton Harrison Tarrant, 28, appeared in court in Christchurch a day later charged with murder.
The New Zealand resident was remanded in custody.
A man with the same name appears to have published a manifesto before the attack outlining his intentions. He identified himself as a 28-year-old Australian citizen and espoused far-right and anti-immigrant ideology.
Three others arrested after the attack are not believed to have been involved, Police Commissioner Bush said.
By Dominic Bailey, David Brown, Salim Qurashi, Debie Loizou, Lucy Rodgers and Prina Shah.