One person who attended Soundsplash festival in Hamilton has been confirmed to have Omicron.
The ministry on Thursday afternoon confirmed five people in Auckland had tested positive for Covid after attending the festival at the weekend.
Whole genome sequencing has confirmed that one of the cases has the Omicron variant, while the other four were being looked into.
So far, 68 people who attended the festival have been identified as close contacts, and the ministry said that number is expected to increase.
Contact tracing staff are working to contact those people. Interviews with the five cases will assist in determining whether they contracted Covid-19 before or while attending the festival, the ministry said
It comes after the festival was listed as a location of interest by the Ministry of Health on Thursday morning.
The ministry on Wednesday afternoon said it had been made aware of a number of cases who attended the festival over the weekend.
Anyone who attended the festival from Friday 21 January at 6:00am to Sunday 23 January at 9:15am is asked to self-monitor for Covid-19 symptoms for 10 days, which is until Wednesday, February 2.
If symptoms develop, the ministry asks those who attended to get a Covid-19 test and stay at home until returning a negative test result.
One of the cases, identified as Emma, told 1News on Wednesday that she started developing symptoms on Monday evening after attending the festival over the weekend.
She says five of her friends had also contracted the virus in connection to the festival and that one case had been confirmed as being the Delta variant of Covid-19.
There were 45 new Covid-19 community cases in New Zealand on Thursday, of which 34 are the Omicron variant of the virus.