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A mid-air collision over Sydney, which resulted in the deaths of two women, involved planes from two different flight training schools.
The women, believed to be in their 20s, were killed when their Cessna hit the rear of a two-storey house in Flame Tree Street, Casula, after colliding with another plane about 11.30am (1.30pm NZST), police say.
The second plane sent a mayday call to Bankstown Airport in the city's southwest before making an emergency landing.
Its two occupants - a 25-year-old pilot and 89-year-old instructor - suffered only minor injuries, the ambulance service said. Their single-engine plane sustained minor damage.
Officials are questioning the pair and have launched an investigation into the accident.
A spokesman for Sydney Flight Training Centre said its plane was the one that landed safely, and had been carrying a student pilot and an instructor.
"The one that landed safely was ours," the spokesman said.
"The other aircraft belonged to another school."
Basair Aviation College confirmed it owned the plane that hit the house, but declined to make immediate comment.
Assistant Police Commissioner Frank Menilli told reporters at Casula that the rear of the house was a mess, and the back patio had been destroyed.
"Both women are deceased," he said of the plane's only occupants.
"The bodies are in situ and it is extremely difficult to actually see their age but I expect they are in their late 20s."
The occupants of the house - Bianca and Steve Condina and their one-week-old baby Aidan - were not home when the incident occurred.
Mrs Condina's father Gino Velerio says he feels blessed his daughter and grandson were not at home.
"She took the baby for a photo with Santa Claus ... some time this morning."
He said Mrs Condina and the baby normally spent most of their time in the kitchen, which is attached to the patio demolished by the plane.
Witness Reg Dawes said the plane appeared totally out of control as it fell to the ground.
"I just seen this single little plane just spiralling right down," Dawes told Australia's Sky News television.
"It made me feel real sick in the gut actually."
Another witness told a local radio station the tail of the plane that crashed was hanging off prior to impact, according to a news.com.au report.
"I was going along the M5 and I've just seen this thing coming down ... the tail was hanging off the back and it's crashed into the back of a house up near Box Road and it's absolutely demolished the back of their house," he was quoted as saying.
Police have sealed off Flame Tree Street, with police and fire personnel still working at the scene of the fatal crash.
Location of the plane crash:
