A man has been charged after allegedly setting off an explosion which caused a fire at his Bunbury home in WA's South West after police knocked on his front door.

Two police officers went to 48-year-old Iain Ross Hudson's home in the Bunbury suburb of Withers on Tuesday afternoon.

While the officers were standing on the home's porch they heard an explosion inside.

Police allege Mr Hudson then tried to flee but was quickly caught by officers.

A second explosion was heard and the house caught on fire.

Mr Hudson and the two officers received medical treatment for minor injuries.

The police investigation is continuing. ( ABC News: Jacqueline Lynch )

Neighbour Donald MacPherson said he heard the explosions at the property next door to his as he was having a New Year's Eve barbeque.

"It blew the doors and windows out … I packed myself," he said.

"It was a real big bang and flames went everywhere … a very big bang.

"All I saw is the door went flying and the two police officers came running back."

Mr MacPherson said he had been unable to stay at his home since the explosion, as there were concerns about whether there had been any impact from the explosions on the structural integrity of his property.

"I was very frightened, I wasn't allowed to stay here last night, just in case something happens," he said.

Donald MacPherson says the explosion blew the property's doors and windows out. ( ABC News: Jacqueline Lynch )

He said the road had been blocked off, with officers working overnight to ensure the fire was extinguished.

Mr Hudson is facing several charges including criminal damage by fire, but has denied causing the explosion.

He appeared in the Bunbury Magistrates Court on Wednesday where he indicted he would be pleading not guilty to the charges.

He told the court he thought it was his mobile phone that exploded.

The man was granted bail and is expected to appear in court again on Thursday.

Bunbury and Arson Squad detectives are continuing their investigation.

Anyone with information on the incident is urged to contact Crime Stoppers.