Four suspects have been taken into custody following the shooting and the gunman has been charged with murder.
"We stand here and condemn, absolutely the attack that occurred today by an extremist, right-wing, violent terrorist", Morrison told a press conference.
"I can't even imagine what would have happened if they were there five minutes earlier", he said on social media.
Taoiseach Leo Varadkar extended his sympathies to those victims and families of the Christchurch attack.
World reacts with sadness and anger to New Zealand mosque attacks
Imran Khan, the President of Pakistan and former first-class cricketer, retweeted the boxer, writing: 'I blame these increasing terror attacks on the current Islamophobia post-9/11 where Islam & 1.3 bn Muslims have collectively been blamed for any act of terror by a Muslim.
"Not only the perpetrators, but also politicians & media that fuel the already escalated Islamophobia and hate in the West are equally responsible for this heinous attack", he tweeted. Terrorism has no race or religion.
"May the victims' souls rest in peace".
A spokeswoman for the police said: "Following on from the horrific attacks on mosques in New Zealand we will be conducting reassurance patrols at mosques across the county". A witness named Mark Nichols told the New Zealand Herald that he heard about five gunshots and that a worshiper returned fire with either a rifle or shotgun.
He said that key points in his radicalisation were the defeat of the French far-right leader Marine Le Pen in 2017 elections, and the death of 11-year-old Ebba Åkerlund in the 2017 Stockholm truck attack.More news: Bloody Sunday: Derry awaits decision on 1972 killings
"We warn the attack is a risky indicator of the dire consequences of escalating hate speech, xenophobia, and the spread of Islamophobia".
In Europe, German Chancellor Angela Merkel said she was deeply saddened: "I mourn with the New Zealanders for their fellow citizens who were attacked and murdered out of racist hatred while peacefully praying in their mosques".
"Prince Philip and I send our condolences to the families and friends of those who have lost their lives", she wrote on Twitter. The queen also paid tribute to emergency services and volunteers supporting the injured.
After the attacks, the New Zealand government adjusted the national safety level from low to high, the first time that the country's threat level has been raised to this level. "Evacuations of properties in the immediate area have taken place as a precaution".
"There can be no place in our societies for the vile ideology that drives and incites hatred and fear. We must all stand together as humans to defeat this evil in all its forms".More news: Huawei Watch GT with 2-Week Battery Life Launched in India
Shortly before the attack began, an anonymous post on the discussion site, 8chan, said the writer was going to "carry out an attack against the invaders" and included links to a Facebook live stream, in which the shooting appeared, and a manifesto.
"This is a location of interest in relation to the serious firearms incident in Christchurch today", the police wrote on Twitter.
Norwegian Prime Minister Erna Solberg said the attack sparked memories of the 2011 massacre of 77 people by extremist Anders Breivik at a left-wing youth gathering on a Norwegian island and with a bomb in Oslo.
"Murder of people at prayer, in their most holy and sacred place, is a depraved and despicable act".More news: LSU’s loss to Florida helps Vols in Championship Game
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