An off-duty firefighter and a passing ambulance crew provided critical help during the early moments of a suspicious fire which gutted a South Dunedin house.
Station Officer Brent Foster was at St Kilda Station when the first call came in, about 7.10pm on Saturday.
As soon as his firetruck left the station, the crew could see thick plumes of dark smoke rising over South Dunedin.
By the time SO Foster arrived at 19 Helena St there were three other fire trucks on their way.
When the St Kilda crew arrived the house was well ablaze.
Fortunately, a passing ambulance crew had stopped, paramedics had checked the house, and were able to indicate it was vacant, SO Foster said.
A crew wearing breathing apparatus broke down the front door and fought the blaze.
Crews were able to contain the fire quickly, using hoses to prevent it spreading to neighbouring houses, but the fire got into the roof and it was midnight before firefighters could finally leave the scene.
The house appeared to have been sparsely occupied and was left about 70% damaged by the blaze, SO Foster said.
It was fortunate there had not been issues with staff or appliances but firefighters had decided against calling out a command unit, which would have made their job easier, as there was uncertainty about if it would have been fully staffed, SO Foster said.
It was not clear how the fire had started and police provided a scene guard overnight until an investigator could attend in the morning.
Fire investigator Scott Cameron said the incident was being treated as suspicious.
A second house fire on the weekend spurred a reminder about the importance of having working smoke alarms.
Station Officer Calvin Harradine, of St Kilda station, said the fire in Glendevon Place was reported about 9.05am yesterday.
A mother and three children evacuated, and did the right thing by getting out and closing the door behind them, SO Harradine said.
The fire started in the kitchen but it was not clear how.
The house received damage that was "not too extensive", SO Harradine said.
Fire Investigator Murray Milne-Maresca said it was not considered suspicious and its circumstances were being investigated.
