Sydney, Mar 22 (IANS/EFE): Australian Prime Minister Julia Gillard Thursday apologized for policies that saw thousands of unwed mothers pressured into giving up their babies for adoption in the middle decades of the 20th century.

"To you, the mothers - who were betrayed by a system that gave you no choice and subjected you to manipulation, mistreatment and malpractice - we apologize," Gillard said in the Great Hall of Parliament House in Canberra.

Amid sobs from some of the 800 victims who attended the speech, the premier said she regretted that the mothers were denied information about their rights that would have helped them make an informed decision.

She also offered an apology to the children taken from their mothers.

"To each of you who were adopted or removed, who were led to believe your mother had rejected you, and who were denied the opportunity to grow up with your family and community of origin, and to connect with your culture, we say sorry," Gillard said.

An investigation by a parliamentary committee found that up to 150,000 adoptions took place in Australia in the period 1951-75.

It was not possible to determine how many mothers were coerced into giving up their newborns, the committee said.

Many of the unwed mothers were drugged, fastened to hospital beds and forced to sign the adoption papers without being able to see their babies who had been given to other parents, in many cases without the proper documentation.

Gillard decried "the bullying arrogance of a society that presumed to know what was best".

The prime minister also apologized to people who were handed over for adoption and suffered sexual abuse in their adoptive families or in orphanages.