New Zealand Prime Minister Jacinda Ardern reacts during a briefing in Wellington, capital of New Zealand, on March 16, 2019. Jacinda Ardern reiterated to the public on Saturday morning that the country's gun law will be changed. Gunmen opened fire in two separate mosques in Christchurch on Friday, killing 49 people and wounding 48 others. (Xinhua/Guo Lei)

CHRISTCHURCH, New Zealand, March 16 (Xinhua) -- New Zealand Prime Minister Jacinda Ardern said on Saturday that the suspect of the deadly mosque attacks used modified semi-automatic weapons.

She told a press conference that there were still 39 people in hospital, 11 of whom in critical conditions.

The prime minister said the two police officers who arrested Brenton Tarrant, a 28-year-old Australian man, deserved plaudits for their bravery.

Tarrant was charged with murder and appeared in court briefly on Saturday morning.

The terrorist attacks left 49 people dead and 48 others wounded in two Christchurch mosques. Tarrant was apprehended along with two other Australian men.

Earlier in the day, Ardern said the country's gun law would be changed.

"Our gun law will be changed" said Ardern, noting that the killers had a legitimate gun license.

Five guns were discovered, two of which were semi-automatic guns, she said. Other weapons and firearms were also retrieved by the police after the attacks on Friday.

Police Commissioner Mike Bush told another press conference that his top priority was on public safety across New Zealand and was supporting the victims and staff involved.

"The investigation into the intelligence failures is also a priority," Bush said.

The police chief was joined by representatives from the agencies working on the ground -- Victim's Support, City Council, Civil Defence, Fire and Emergency and the Defence Force.

Bush acknowledged the bravery of the public, police officers and emergency responders.

He said the arrest took 36 minutes from the first emergency call.

Christchurch Mayor Lianne Dalziel on Saturday extended her condolences to the victims and their families and people who are affected by the attacks.

"Our thoughts go to the victims and their families and everyone that being affect," Dalziel said. She also acknowledged the extraordinary response from the police and first responders.

"An attack on the Muslin community is an attack on us, on Christchurch and on New Zealand," Dalziel said.

She believed that Christchurch people will go through this together by "looking after each other ... in many diverse communities in our city."

Calling the event "an unspeakable tragedy," the mayor told Xinhua, "We need to make sure that everyone feels safe, everyone feels welcome and everyone feels a part of the city."

Major public events during the weekend have all been cancelled across New Zealand after the attacks. Flags were flown at half-mast in government buildings to mourn the victims.