Lives could have been lost after a group of young men set off fireworks causing a pile of rubbish next to a house to go up in flames, police say.
Emergency services were called to the flat in Castle Street in Dunedin's student quarter about midnight.
Senior Sergeant Craig Dinnissen said the flatmates awoke to find the fire.
"A group of young males have set off fireworks down an alley way to a house aiming them at a pile of rubbish, the rubbish was piled up against the house and has caught fire," he said.
"The tenants woke and put the fire out."
Fire and Emergency was also called and sent two fire engines to the house.
Fireworks were also later shot at the attending police officers.
"While police were speaking with the tenants another group of males shot fireworks into the same area," Dinnissen said.
"They then continued to fire them at police. All males ran off."
The young men were yet to be located.
The incident gave a timely reminder ahead of Guy Fawkes celebrations over the weekend, he said.
"Police are urging people to treat [fireworks] with respect and common sense unlike the moronic acts displayed by this group of males. If the fire had gone unnoticed this could have led to loss of life.
"To then aim fireworks at attending staff or anybody is beyond comprehension."