A teen phoned emergency services after his girlfriend was critically injured when they both fell through the roof of an abandoned wool factory yesterday.
The young man called for help from his cellphone at 4.45am after the two fell through the "brittle" fibrolite roof of the Manukau Knitting Mills in Howick.
The girl was critically injured, said Howick Fire Station officer Rowan Hegley.
"God knows what they were doing," he said of the couple, who were believed to be in their late teens.
"They had dropped 5-6m on to a concrete floor. It also had some steel machinery, which I suspect they hit," he said.