Two people have died in a house fire in Dunedin this morning.

Four fire crews remain at the scene on Wesley St, where a blaze broke out shortly around 5.15am.

Fire communications spokesperson Rewai Grace said the first firefighters arrived at the scene at 5.18am.

"On the way there, we noticed there was, unfortunately, a good glow in the morning sky, so we called in another engine," he said.

The two-storey house was well ablaze upon their arrival, he said.

Grace said crews remained at the scene where they were working to get the fire under control.

They would be there for most of the day.

Fire investigators would also head to the scene once it was determined the property was safe for entry.

"Once it's safe to do so we'll start the investigation process."