Police also urged all mosques in New Zealand to close their doors and asked residents to refrain from visiting.
Four people, one woman and three men, have been arrested over the horrific shooting so far, which is believed to have killed up to 30 people. "For the person who perpetuated this violence it is not". It was an unprecedented act of violence.
A video has surfaced online of the gunman's rampage. Don't do it. Don't watch it.
New Zealand Muslim communities expressed shock and sadness at the unfolding event. What a awful day.
Tarrant posted photos to his now-suspended Twitter account of what appears to be guns, ammunition and a military-style vest.
Reports two mosques were targeted.
"Again, we are unsure if there are any other locations outside of that area that are under threat".
Canterbury Police NZ tweeted: "We have a critical incident in Deans Ave Christchurch".
AOS (Armed Offenders Squad) push back members of the public following a shooting at the Masjid Al Noor mosque in Christchurch, New Zealand, March 15, 2019. Police also advised all mosques nationally to lock their doors.
An eyewitness told Radio New Zealand he heard shots fired and four people lying on the ground, with "blood everywhere", reported news agency AFP.
Apparently filmed from a head camera, it shows a man in combat gear driving to the Al Noor Mosque in central Christchurch.
Police officials did not immediately comment on whether the incident took place in the mosques or nearby.
Ten emergency service vehicles are at the scene and police say it is an "evolving situation".
The suspect was seen wearing dark clothing, and in the footage an officer appears to have hit the person. The Christchurch Hospital will be dedicated to be treating those injured in the incident.
At least 40 are confirmed killed after gunmen opened fire in two mosques in the city in a coordinated series of terrorist attacks.
The Bangladesh cricket team was at the mosque for Friday prayer when the shooting started.
Police have ordered schools to go into lockdown and urged anyone in central Christchurch to stay indoors.
Bush also said it should not be assumed the attack was isolated to Christchurch. "Armed police have been deployed".
The city has been put in lockdown as a manhunt ensues. "We will continue working directly with New Zealand police as their response and investigation continues".
A second shooting took place at a mosque in the suburb of Linwood.
"The players are shaken up but fine", Villavarayen was quoted as saying.
The injured were very quiet, Jellie said. They didn't see anything but heard gunshots.