Apart from numerous witness reports of casualties, a reporter following the Bangladesh cricket team, who are now in New Zealand, tweeted that the team had "escaped from a mosque near Hagley Park where there were active shooters".
There was no official information on casualties but the New Zealand Herald said at least one person was killed.
They didn't see anything but heard gunshots.
The Bangladesh cricket team is in Christchurch to play New Zealand in a third cricket test starting on Saturday. In Christchurch ahead of a scheduled match Saturday against the host nation, they went to pray at one of the two mosques attacked but managed to make it back safely to their hotel.
"By the time I got close to the park, the players had disembarked from the bus, they were running towards me and just telling me to get out of there. I'm speaking from what I've heard".
Opening batsman Tamim Iqbal said on Twitter the experience had been "frightening".
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Police said a shooter also entered another mosque at Linwood Avenue, and confirmed there had been multiple fatalities.
One witness told stuff.co.nz he was praying in the Deans Ave mosque when he heard shooting and saw his wife lying dead on the footpath outside when he fled.
'We are shocked and appalled as I am sure all New Zealanders are. "The players were stranded on the bus and called for help", he said.
"FICA has been in contact with the New Zealand Cricket Players' Association and Cricketers' Welfare Association of Bangladesh and full support has been offered to the Bangladesh players and the touring squad on the ground".
People in center of the city should stay indoors, police said.
ESPN Cricinfo reporter Mohammad Isam filmed members of the Bangladesh team hurrying away from the mosque through Hagley Park after the incident. The people who were the subject of this attack today, New Zealand is their home, they should be safe here.
"Many of those who would have been affected by this shooting may be migrants to New Zealand".
He added: "The players were breaking down, they had seen way too much in the 15 minutes they were held up in the bus, there was no security because it is such a peaceful country".