"We strongly believe we stopped him on the way to a further attack," Bush said. "So lives were saved."
He declined to state the third location, as to not "traumatize" more people.
On Friday, March 15, a gunman opened fire at two mosques back-to-back in Christchurch, New Zealand, killing 50 people and wounding more than 40 others.
Funerals for the victims began on Wednesday at Christchurchs Memorial Park Cemetery, Reuters reported .
As of Tuesday night, 21 victims were "formally identified," Bush said during his press conference. He said he expected that 27 would be "identified by midday."
Bush said he hoped that the majority would be identified by the end of Wednesday, and he stressed that the identification of the victims was "an absolute priority for family reasons, compassionate reasons, and for cultural reasons."
Bush explained that the process of identifying the bodies was also very important to the prosecution of the suspect, "as correct identification is required as part of the investigation and is necessary to prove a charge of murder."
The suspect, 28-year-old Brenton Tarrant, who was born in Australia and is a suspected white supremacist, was charged with murder. He will be back in court on April 5 where he could face additional charges.
Bush also gave further details of the timeline of first responders, saying that police had the suspect in custody and at the precinct within 36 minutes; he was apprehended 21 minutes after the first emergency call.
Video of the arrest shows a police car rammed into the side of the suspect's car, with two armed officers apprehending the alleged offender.
The country has been mourning, following the deadliest mass shooting in its history, which Prime Minister Jacinda Ardern called an "act of terrorism."