Soundsplash festival in Hamilton has been identified as a location of interest after a number of Covid-19 cases attended the event over the weekend, the Ministry of Health said on Wednesday night.
"This afternoon the Ministry of Health has been made aware of a number of cases who attended a festival in Hamilton over the weekend," the ministry said in a statement.
"Public health officials are currently assessing the potential exposure and expect to publish a location of interest early tomorrow, which will include health advice for those who were at the event."
One of the cases, who only wants to be identified as Emma, told 1News she started developing symptoms on Monday evening after attending the festival over the weekend.
She says five of her friends have also contracted the virus in connection to the festival.
One case has been confirmed as being the Delta variant of Covid-19. The others are unknown at this stage.
In a statement on Instagram, Soundsplash organisers said they were aware the Ministry of Health had told media about the cases at the festival.
"At this stage, the organisers of Soundsplash are awaiting official communication from the Ministry of Health on this matter... we will provide further updates once we receive official advice."
It encouraged people to isolate and get tested immediately if they had Covid-19 symptoms.
It comes as there were 23 cases of Covid-19 recorded in the community on Wednesday, 15 of which were the Omicron variant.
A descendant of the Omicron variant that is harder to detect has also been found in a "small number" of Kiwi border workers and their close contacts, the Ministry of Health confirmed.
This version of the coronavirus, which scientists call BA.2, is widely considered stealthier than the original version of Omicron (BA.1) because particular genetic traits make it somewhat harder to detect. Some scientists worry it could also be more contagious.
More details of the three staged plan the Government will roll out as Omicron spreads around New Zealand were released on Wednesday.