Peneha said he then went into the mosque to try and help.
Police advised people to stay away from mosques.
At least 40 are believed to have been injured after the mass shooting.
"The situation is still unfolding but our thoughts and prayers are with our Kiwi cousins".More news: Trump slams handling of Brexit by UK's May
Police said they were in the process of mobilizing every national police resource to respond to the incident.
"I was in the mosque". The gunmen came from the backside.
Another witness told TVNZ he heard gunfire at around 1.45pm local time.
He said some managed to escape through windows and doors but "many people had been hit, some as young as 16".
"I didn't think I'd live to see this happening in my country", she said.
"The second shot, I run, lots of people were sitting on the floor", he told media.
According to a report from Radio NZ, Adam Ali was praying at the Linwood Masjid when a gunman entered the mosque and opened fire. We are still waiting for official confirmation of the death toll.More news: Slack mobile app gets its own 'dark mode' in latest update
"I didn't get a glimpse of the gunman as I was in the next room, but all of a sudden we heard the shots being fired and people just started running for their lives. I ran around the door, I ran behind the mosque".
We're working to gather more information.
A Christchurch Hospital spokesman said some shooting victims were being treated at the emergency department but he could not provide numbers, because the hospital was in lockdown. They said schools in the city had been placed on lockdown and urged people to stay indoors.
Christchurch City Council tweeted that it was locking down a "number of central city buildings, including the Civic Offices and Central Library".
Christchurch, located on New Zealand's South Island, is the third-largest city in the country with a population of just over 400,000.
He said he chose New Zealand because of its location, to show that even the most remote parts of the world were not free of "mass immigration".More news: Trends driving the Internet of Things Devices market in the digital ecosystem