49 people have been killed after a terrorist attack on two mosques in Christchurch in New Zealand.
20 others are seriously injured after gunmen started shooting at worshippers.
Four people have been arrested - one of them is an Australian-born citizen.
New Zealand's security threat level has been increased to "high"
The prime minister says it's one of the country's "darkest days".
Former Irish rugby player Ronan O'Gara lives in New Zealand and is the current coach of the Crusaders who are based in Christchurch.
He says it has been an extremely difficult day for people right across the city.
“Of all the cities in the world, I suppose, Christchurch has had its own adversity with earthquakes – but people here are very resilient and very nice and now this out of the blue,” he said.
“Yeah the boys are shook. There is no doubt about it. Everyone is shook.
“I am not from there obviously, but it is a lovely city and when you live there it becomes your home so it has been a very surreal day.”