So far, police have arrested four people in connection with the attack on two Christchurch mosques -- three men and one woman.
In a social media post just before the attack, an account that is believed to belong to one of the attackers posted a link to an 87-page manifesto that was filled with anti-immigrant, anti-Muslim ideas and explanations for an attack. The manifesto was not signed.
TVNZ journalist Anna Burns-Francis told CNN at least one of the shooters is believed to be an Australian national, while a witness from the scene described a man "white, aged in his 30s or 40s and wearing a uniform."
CNN has not been able to independently confirm any information about any of the attackers at this stage.