Three people have been assessed by paramedics after the fire on Whale Island Way, which caused serious damage to the back of the property and spread to a neighbouring house.
Residents living nearby have been evacuated and taken to HMS Excellent.
Luckily there have not been serious injuries and the fire was put out earlier this afternoon – you can read the latest updates on our live blog.
The incident sparked a huge emergency response and here are a few photos which show the amazing work carried out by our police, ambulance and fire services this afternoon.
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5. Portsmouth house fire
Three people were assessed by paramedics after the explosion. Picture: Habibur Rahman Photo: Habibur Rahman
6. Portsmouth house fire
Police and fire crews wait at the scene of the house fire. Picture: Habibur Rahman Photo: Habibur Rahman
7. Portsmouth house fire
Fire crews at the scene at Whale Island Way, Portsmouth. Picture: Habibur Rahman Photo: Habibur Rahman
8. Portsmouth house fire
Police helped to evacuate nearby residents. Picture: Habibur Rahman Photo: Habibur Rahman