Daoud Nabi had lived in New Zealand for more than 40 years after fleeing Afghanistan as a refugee in the late 1970s, and believed his adopted home to be a "slice of paradise", his son Omar told AFP.
Two mosques were targeted in the attack.
Muath Elayyan, Mohammed's brother, told the Associated Press his brother helped establish the mosque a year after arriving in New Zealand, where he teaches engineering at a university and runs a consultancy.
"He had a big gun.He came and started shooting everyone in the mosque, everywhere", said the man, Ahmad Al-Mahmoud. "He enjoyed freedom there and never complained about anything", Muath said.
In a video filmed from his hospital bed Alsati asked people to "please pray for me and my daughter", who has been flown to Auckland for treatment.
Over the weekend Palestinians in the West Bank and Gaza held vigils to honor the victims of the massacre, in which 49 people were killed. The courtroom was closed to the public because of the heightened security risk, New Zealand police said. "To see so many innocent lives taken so callously and cruelly in this place of sanctuary is totally unacceptable".
Some families and friends of the missing continued to wait for information about their loved ones as night fell on Saturday local time and a tight-knit community of Muslims mourned alongside the country and the world.
Speaking to reporters later, Ardern said the country's gun laws will change in the aftermath of the attack on Christchurch mosques by Brendon Terrant, the Aurtralia-born terrorist behind the carnage.
The suspect, Brenton Harrison Tarrant, appeared in court Saturday, charged with one count of murder.
"Many of the people require multiple trips to the theatre to deal with the complex series of injuries they have", said Christchurch Hospital's Chief of Surgery Greg Robertson.
Ardern said the suspect traveled around the world and was in New Zealand sporadically.
"I have been deeply saddened by the appalling events in Christchurch today", she said. Footage of the attack on one of the mosques was broadcast live on Facebook, and a "manifesto" denouncing immigrants as "invaders" was also posted online via links to related social media accounts.
Authorities declined to discuss potential motives for the attack.
Tarrant did not have a criminal history and was not on any watchlists in New Zealand or Australia.
Two other suspected accomplices have also been arrested.
Brenton Tarrant, 28, used five guns - "two semi-automatic weapons, two shotguns and a lever-action firearm", the prime minister said.
Her father Waseem, 33, the brother of Mr Daraghmeh, is said to be in a stable condition. Authorities were working to find out how he had obtained the weapons and a license, and how he was able to enter the country to carry out the attack, she said.