Two young girls and a woman are fighting for life after a suspicious house fire in Melbourne.

Emergency services were called to a two-storey townhouse on Terrigal Street in Chadstone about 9.40pm yesterday.

Firefighters arrived to find flames coming out of the roof and forced their way into the home, where they found three people inside.

They pulled two primary-school-aged girls and a woman in her 30s from the home.

The girls were taken to the Royal Children’s Hospital and the woman was taken to the Alfred Hospital, all in critical condition.

Firefighters brought the fire under control in about 35 minutes.

According to Fire Rescue Victoria, the blaze involved the bedrooms and ensuite on the second floor.

The fire had penetrated the roof and caused some structural collapse.

The remainder of the house suffered smoke and water damage.

Police are treating the fire as suspicious as they investigate its cause.

A crime scene has been established and an arson chemist will assess the home.

Anyone who witnessed the fire or has any vision is urged to contact Crime Stoppers.