Australia said Wednesday it now believed many of its citizens aboard 10 flights out of Qatar were strip searched and subjected to examinations in what its foreign minister described as a "grossly disturbing" and "offensive" invasion.

Foreign Minister Marise Payne now says the number of allegedly "assaulted" Australian women has grown and Australian citizens on 10 flights about to depart were subject to the tests. She said earlier this week that 18 of its citizens were taken from a Qatar Airlines plane about to take off for Australia and subjected to internal examinations carried out on the tarmac.

The news of the searches and examinations has triggered indignation in Australia - with opposition politicians calling it sexual assault. Qatar says the women were examined to see if they had recently given birth. A newborn was found abandoned in an airport toilet - sparking the investigations. Hamad International Airport authorities were searching for the mother of a prematurely born baby abandoned in one of the airport's toilets, they say.

Payne said Wednesday new information greatly expanded the number of women thought affected as Qatar's government said it had begun an investigation into the incident.

Payne told Australia's Senate that women on "10 aircraft in total" had been subject to the searches, which she has described as "grossly disturbing" and "offensive...We became aware of that yesterday through advice from our post in Doha."

Payne added that other countries had concerns about the incident that occurred Oct. 2. The Agence France-Presse news agency reported one French woman was among them. Payne didn't say where the other flights were headed.

Qatar's prime minister has asked for an investigation into the incident, the government's communications office told Reuters news agency in a statement Tuesday.

The newborn, a baby girl, was found in a plastic bag in a rubbish bin in "what appeared to be a shocking and appalling attempt to kill her," the statement said, adding the action was an "egregious and life-threatening violation of the law."

Australia news media had previously reported that all women passengers who had boarded an aircraft from Doha to Sydney were ordered to disembark without reason.

The women were led to an ambulance on the tarmac and ordered to remove their clothes and underwear before being internally examined. Qatari authorities, who apologized and said the infant was safe and in medical care in Doha, said they had begun an inquiry into the strip-searching.

According to Australia's foreign secretary Frances Adamson, the incident "is not - by any standard - normal behavior and the Qataris recognize that, and are appalled by it, do not want it to happen again," BBC quoted Adamson as saying in a Senate hearing Wednesday.

Meanwhile, the Transport Workers' Union of New South Wales, whose members service Qatar Airways aircraft, said it was looking to file an industrial action against the Qatari airline for what it describes as a "brutal attack" on the human rights of the Australian female passengers.