According to Australian authorities, a landslide slammed a British family on vacation in Sydney, killing the father and his nine-year-old boy and gravely injuring the mother and another kid.

The family of five was caught in the avalanche on Monday while hiking along a popular trail in Australia's the Blue Mountains, west of Sydney.

On Tuesday, police said crews were still attempting to collect the father and son's bodies from the area.

On Monday evening, the authorities said rescuers took the mother and her 14-year-old son to a Sydney hospital. They both underwent surgery on Tuesday and were in critical condition.

The couple's 15-year-old daughter sustained no injuries and was escorted from the trail by emergency personnel, according to a police spokesperson.

The British consulate and social services are assisting her.

Local police in the Blue Mountains were investigating the landslide and preparing a report on the two fatalities for the coroner.

The family's identity has not been disclosed.

Sydney has been experiencing torrential rainfall in recent weeks, with some districts in the city's west being damaged by flash flooding and severe storms.