Detective Acting Senior Sergeant Ralph Tyler of the Casey CIU said he was amazed at the number of people who flocked to the fire scenes.

"I was on duty and it was a problem. It was almost like you could have sold hotdogs and made a fortune around those areas," he said.

"When roads are partially blocked by onlookers it makes it even harder to get emergency services through.

"In Harkaway Road near King Road, for example, there were lines of cars. No doubt some simply went to have a bit of a gawk."

When the Journal went to the scene of the Narre Warren South fire on Monday, curious onlookers were slowly driving past destroyed homes in Langbourne Drive.

"It's been just like a parade," said annoyed resident Rohan, who did not want his surname published.

"There have been a 100 people at a time walking in the burnt vacant land behind my home. It's ridiculous and insensitive."

At one stage, police had to block both ends of the street off to deter stickybeaks, he said.

Fellow Langbourne Drive resident Janeen Cooke was appalled by the number of people who flocked to gawk when residents were busy battling the blaze.

"Some were even drinking beer on the side."

But Ms Cooke said there were also plenty of good Samaritans who did not live nearby but came to lend a hand.

"One woman drove from Fountain Gate to help. Total strangers turned up carrying buckets."

Narre Warren North resident Amanda Hebdige, whose fence was burnt in a separate fire that day, was also thankful for unexpected helping hands.

"Neighbours I know, as well as complete strangers, were in my backyard putting out spot fires around the fenceline, pergola and next to our garage," Ms Hebdige said.

Cranbourne North resident Jackie Quigley, whose pool was emptied as part of an intense firefighting effort, also condemned onlookers for blocking exit routes.

"If our house had gone up, we wouldn't have been able to get out because of the onlookers."