Police have evacuated an area near Bacchus Marsh, north-west of Melbourne, after two people were injured in explosions believed to be caused by a ruptured gas pipe.
A teenage boy has been taken to hospital in a serious condition with burns and a man has minor injuries, after the incident at Maddingley around 1:30pm.
Police believe a gas pipe ruptured at a worksite, causing two explosions.
The Bacchus Marsh Secondary College and Bacchus Marsh Grammar were evacuated, along with the Providence Catholic nursing home.
Michelle Smith works nearby and has told ABC Radio Melbourne she heard several loud explosions.
"We all ran out, there was plumes of dust and I thought it may have been a car accident," she said.
"I looked down the street and all of the stormwater drain covers were off, they had been blown."
The Country Fire Authority has sent 13 units to the area to investigate the source of the leak.
Worksafe is also investigating.
A relief centre for people who have been evacuated has opened at the Lerderderg Library at 215 Main Street, Bacchus Marsh.