Qatar apologises and promises to investigate after women strip-searched at Doha airport

Qatar has apologised after female passengers on a flight to Sydney were subjected to invasive examinations following the discovery of a newborn baby in a terminal toilet.

The women, including 13 Australians, were searched at Doha's Hamad International Airport on 2 October after the Qatar Airways flight was delayed.

Qatar offered no immediate explanation about how officials decided to examine the women.

Qatar's government communications office issued a statement early on Wednesday that authorities discovered the newborn "concealed in a plastic bag and buried under garbage" at the airport.

It called the discovery an "egregious and life-threatening violation of the law".

The statement said officials searched for the baby's parents, "including on flights in the vicinity of where the newborn was found".

The government said: "While the aim of the urgently decided search was to prevent the perpetrators of the horrible crime from escaping, the state of Qatar regrets any distress or infringement on the personal freedoms of any traveller caused by this action."

Authorities have begun an investigation into the treatment of the women with the results set to be shared internationally.

Human rights activists describe such examinations conducted under duress as equivalent to sexual assault.

In Qatar, like much of the Middle East, sex outside of marriage is a criminal act.

Migrant workers in the past have hidden pregnancies and tried to travel abroad to give birth, and others have abandoned their babies anonymously to avoid prison.

Australia has described the situation as inappropriate and beyond circumstances in which the women could give free and informed consent. The country's federal police are also examining the matter.

On Monday foreign minister Marise Payne called the searches "grossly disturbing, offensive [and] concerning."

She added: "It's not something that I've ever heard of occurring in my life, in any context.

"We have made our views very clear to the Qatari authorities on this matter."

Australia's Seven Network News reported the women were examined in an ambulance on the tarmac.