Two teenagers will undergo surgery for broken bones after a car they were in ploughed through the front yard of a home in Perth's south-east and landed on top of a boundary fence late on Friday night.
One of the bedroom windows on the Piara Waters home was smashed and debris was sent flying across the room, through a brick wall and into the adjacent room.
No-one was in the rooms when the crash occurred.
Police said the car was being driven by a 17-year-old girl and three other people were in the vehicle at the time.
Two are recovering in Royal Perth Hospital, while the other two have been discharged after being conveyed to Fiona Stanley Hospital.
Resident Ronwyn Camp was the only person at home when the crashed happened.
She said the car smashed through the wall of a bedroom where her 31-year-old daughter Jenae Finn slept when she visited.
"That's actually my eldest daughter's bedroom. She often comes over and has a sleepover, and she always goes and sleeps in her room," she said.
"Fortunately, there was no-one here except me."
Skid marks could be seen veering off the road just before the roundabout approaching Ms Camp's house.
The car crashed through the front boundary wall before ending up atop a side wall separating the neighbouring property.
Ms Camp said the family decided to have the wall built around the front of the house over fears of just such an accident due to their proximity to a roundabout.
She said it was difficult to imagine how bad the damage would have been if the wall had not absorbed some of the impact.
"I was absolutely gobsmacked when I saw the extent of the damage to the house … and even more shocked when I went through the house and had a look at the bedroom," Ms Camp said.
Ms Camp said she slept through the incident and was only made aware of what had happened through a text on Saturday morning.
"I woke up to a message this morning from the police telling me that a car had hit the front wall," she said.
"One of the first things I had to ask the police this morning was if there were any fatalities because of the extent of the damage.
"Fortunately, there weren't. Luckily, nobody was killed through all of this."
Police are investigating the crash.
