Police said the attack took place at a Countdown supermarket in central Dunedin, on New Zealand's southern island, at about 2:30 p.m. local time (0230 GMT/UTC).
Witnesses told local media a man carrying two knives had stabbed staff, as well as bystanders who tried to stop him and pin him down.
People reported a chaotic scene as people began screaming and running toward the store exits.
Health authorities said three of the wounded individuals had been admitted to intensive care, with one admitted to a general ward and the other discharged.
Police took a suspect into custody, and were apparently not seeking anyone else in relation to the attackImage: Otago Daily Times/AP/picture alliance
Prime Minister Jacinda Ardern said police had assured her the Dunedin attack did not have further security implications.
"At this stage, there's nothing to suggest from the police's perspective that this is what they would define as a domestic terror event," she told reporters.
The prime minister added that police were not seeking anyone else in relation to the incident, and thanked customers who had tried to intervene.
"I want to acknowledge early reports of bystanders who have taken action in order to protect those around them [...] these are courageous acts and we are thinking of the families," she said.
The supermarket chain said its staff had been "shocked and devastated" by the attack.
Christchurch gunman sentencing
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"Our priority right now is our injured team members and caring for our wider team in the wake of this extremely traumatic event," said a message on the company website.
"We are deeply upset that customers who tried to help our team members were also injured."
Christchurch grieves right-wing terror attack
New Zealand and the world reeled from a right-wing mosque massacre on Friday. The terror shooting left behind grievous scenes.
Image: Reuters/H. Nicholls
'There was blood everywhere'
A witness said "there was blood everywhere," after a right-wing terror attack on two New Zealand mosques killed 50 on Friday. Another witness saw a man in black enter the Al Noor mosque during prayers in Christchurch and heard dozens of shots before fleeing, adding that he saw several dead on the scene. As of Friday afternoon 48 people, including children, were being treated for gunshot wounds.
Image: Reuters/SNPA/M. Hunter
Twin attacks target two mosques
Police asked all mosques across New Zealand to close while they hunted those responsible for the twin attacks. Al Noor mosque (above) is approximately 7 kilometers across the city from Linwood Mosque, the site of the second shooting.
Image: Reuters/SNPA/M. Hunter
City on lockdown
Police initially arrested four people, two of them armed, and later charged one with murder. An Australian man, Brenton Tarrant, is alleged to have filmed himself carrying out the shooting and streamed it on social media. A manifesto was also published online, praising white men who had carried out similar massacres. It also called US President Donald Trump a "symbol of renewed white identity."
Image: Reuters
'Atmosphere of fear'
The attacker's stated aim was to "create an atmosphere of fear" and "incite violence" against Muslims. Police said they recovered several guns from the mosques and two explosive devices in two vehicles at the scene. While the suspects were unknown to police, they said the attack appeared to have been well planned. Police were not searching for other suspects, but were on alert
Image: Reuters
Narrow escape as shock spreads
The world reacted in shock. Anger spread in some countries and security was heightened at prayers at this mosque in Bangladesh as news was released that the Bangladeshi cricket team had narrowly escaped the shooting. The players had arrived at one of the mosques as the attack was unfolding when they heard gunshots.
Image: Reuters/M. Ponir Hossain
'One of New Zealand's darkest days'
New Zealand Prime Minister Jacinda Ardern described the attack as terrorism, calling it "one of New Zealand’s darkest days." "Many directly affected by this shooting may be migrants to New Zealand, they may even be refugees here...They are us. The person who has perpetuated this violence against us is not," she said.
Image: Getty Images/M. Tantrum
World in mourning
Friday sermons across the world were dominated by grief and prayers for the lives lost in the attack. Prayers at the Al Aqsa mosque in Jerusalem (here) mourned the victims. Demonstrations in other major cities such as Sydney, Istanbul and London condemned global terror.
Image: picture-alliance/AA/F. Abu Rmeleh
Dismay at 'senseless violence'
Leaders across the world expressed solidarity with the victims and their families, including Labour leader Jeremy Corbyn outside New Zealand House in London. Chancellor Angela Merkel expressed solidarity against "racist hatred," and Foreign Minister Heiko Maas called it an "attack on all of us." Queen Elizabeth was "deeply saddened," while other leaders expressed their outrage at hate speech.
