A man who was inside a Christchurch mosque when it was attacked has been hailed as a hero for confronting the gunman, chasing him off and preventing more deaths.

Key points: Abdul Aziz distracted the gunman as his youngest sons begged him to return inside the Linwood mosque

Abdul Aziz distracted the gunman as his youngest sons begged him to return inside the Linwood mosque He found a discarded gun and pulled the trigger, but it was empty

He found a discarded gun and pulled the trigger, but it was empty Mr Aziz was born in Afghanistan but left as a refugee and lived in Australia for 25 years

Abdul Aziz did not hide when the shooter advanced toward the Linwood mosque during Friday prayers, killing those in his path.

Instead, he picked up the first thing he could find — a credit card machine — and ran outside screaming "Come here!"

Mr Aziz, 48, has been praised for saving many people inside by leading the gunman on a cat-and-mouse chase before scaring him into speeding away in his car.

But Mr Aziz, whose four sons and dozens of others remained in the mosque while he faced off with the gunman, said he thinks it is what anyone would have done.

Abdul Aziz, 48, is being hailed as a hero for preventing more deaths during Friday prayers at the Linwood mosque. ( AP: Vincent Thian )

'This is a killer'

The gunman killed 50 people in terror attacks at two mosques in the deadliest mass shooting in New Zealand's modern history.

He is believed to have killed 42 people at the Al Noor mosque before driving about 5 kilometres across town and attacking the Linwood mosque, where he killed seven more people. One person died later in hospital.

Australian Brenton Tarrant, 28, has been charged with one count of murder over the slayings and a judge said on Saturday that it was reasonable to assume more charges would follow.

Latef Alabi, the Linwood mosque's acting imam, said the death toll would have been far higher at the Linwood mosque if it was not for Mr Aziz.

Mr Alabi said he heard a voice outside the mosque about 1:55 pm (local time) and stopped the prayer he was leading and peeked out of the window.

He saw a man wearing black military-style gear and a helmet holding a large gun, and assumed it was a police officer. Then he saw two bodies and heard the gunman yelling obscenities.

"I realised this is something else. This is a killer," he said.

He yelled at the congregation of more than 80 to get down. They hesitated. A shot rang out, a window shattered and a body fell.

"Then this brother came over. He went after him, and he managed to overpower him, and that's how we were saved," Mr Alabi said, referring to Mr Aziz.

"Otherwise, if he managed to come into the mosque, then we would all probably be gone."

Members of the public mourn and lay floral tributes at a memorial wall in the Christchurch Botanical Gardens near the scene of mass killings. ( ABC News: Brendan Esposito )

'Cat-and-mouse' chase

Mr Aziz said as he ran outside screaming, he was hoping to distract the attacker.

He said the gunman ran back to his car to get another gun, and Mr Aziz hurled the credit card machine at him.

He said he could hear his two youngest sons, aged 11 and five, urging him to come back inside.

The gunman returned and fired. Mr Aziz said he ran, weaving through cars parked in the driveway, which prevented the gunman from getting a clean shot.

Then Mr Aziz spotted a gun that had been discarded by the attacker and picked it up, pointed it and squeezed the trigger. It was empty.

He said the gunman ran back to the car for a second time, likely to grab yet another weapon.

"He gets into his car and I just got the gun and threw it on his window like an arrow and blasted his window," he said.

The windshield shattered, Mr Aziz said.

"That's why he got scared."

He said the gunman was cursing at him and yelled that he was going to kill them all.

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But he drove away and Mr Aziz said he chased the car down the street to a red light, before it made a U-turn and sped away.

Online videos indicate police officers managed to force the car from the road and drag out the suspect soon after.

Not his time to die

Originally from Kabul, Afghanistan, Mr Aziz said he left as a refugee when he was a boy and lived for more than 25 years in Australia before moving to New Zealand a couple of years ago.

"I've been to a lot of countries and this is one of the beautiful ones," he said.

And, he always thought, a peaceful one as well.

Mr Aziz said he did not feel fear or much of anything when facing the gunman — it was like he was on autopilot.

And he believes that God, that Allah, did not think it was his time to die.

The killings, which were live streamed by the alleged gunman on social media, shocked New Zealand and the world. ( ABC: Brendan Esposito )

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