The world watched in shock as news began coming in from New Zealand\u2019s Christchurch city reporting multiple deaths in separate mosques as gunmen opened fire at people inside on Friday morning, the busiest time for prayers. The shootings took place at the Linwood Masjid in Linwood and Masjid al Noor mosque at Deans Avenue, CNN reported. Informing that four people - three men and one woman - are in police custody in relation to the shootings, New Zealand Police Commissioner Mike Bush said that they were still unsure if there are more locations under threat and whether the four detained persons were involved in the attack. A local resident living near the Masjid al Noor mosque on Deans Avenue described the gunman as "white, aged in his 30s or 40s and wearing a uniform". However, the uniform remains unidentified. Multiple casualties were confirmed by authorities in the shooting incidents and it is now confirmed that 40 people were killed in Christchurch mosque attack in New Zealand and 20 were injured. What has happened in Christchurch is an extraordinary act of unprecedented violence. It has no place in New Zealand. Many of those affected will be members of our migrant communities \u2013 New Zealand is their home \u2013 they are us. \u2014 Jacinda Ardern (@jacindaardern) March 15, 2019 At least one of the shooters is an Australian, Australia's Prime Minister Scott Morrison said. The PM said that the attacker was an "extremist, right-wing, violent terrorist" and an Australian citizen, reported AFP. Several improvised explosive devices which were also found attached to vehicles as part of the terror attack have been neutralised \u2018by the defense force\u2019, the police told media. As of now, the officials have refused to share the motives and what caused the attack. However, it was reported that prior to the attack, a social media account believed to be that of one of the attackers shared a link to an 87-page manifesto. The document, riddled with anti-Muslim anti-immigrant ideas and explanations for an attack, was however, not signed. A viral livestream video which is said to be that of the attack has been removed from Facebook. It showed what appeared to be the gunman opening fire in the Christchurch Mosque; it is yet to be verified by authorities. This has also again raised questions on the tech companies\u2019 stand on the violent content and how they intend to block it. READ ALSO |\u00a0 New Zealand mosque shooting Live Updates: Police order lockdown, Bangladesh cricket team escapes\u00a0unhurt "New Zealand Police alerted us to a video on Facebook shortly after the livestream commenced and we removed both the shooter's Facebook account and the video. We're also removing any praise or support for the crime and the shooter or shooters as soon as we're aware," a spokesperson for Facebook New Zealand, Mia Garlick said in a statement. Many dead in New Zealand shooting at two mosques during Friday prayers pic.twitter.com\/HrIm13ltMJ \u2014 Reuters Top News (@Reuters) March 15, 2019 New Zealand Prime Minister Jacinda Ardern described the attack as "one of New Zealand's darkest days" in a press conference. Authorities have deemed the attack as ongoing and asked the Christchurch residents to not step outside and keep watch on the police website and social media for updates. However, lockdown on schools in Christchurch has been lifted. The police in US cities such as Los Angeles, New York and Minneapolis have also beefed up security at mosques after the attack was reported.