T Anantharajah, one of those who demonstrated yesterday, told media here that his three children aged 12, 10 and 8 respectively had been forcibly taken away by the Norwegian authorities and placed under the care of foster families.
Anantharajah said that aggrieved parents from at least 60 Sri Lankan Tamil families would soon launch a hunger strike in Oslo against the Norwegian authorities.
However, the Norwegian embassy said the country's child welfare service step in when measures at home are not sufficient to meet a child's need.
"Placing a child in care is a serious step and can only be used when serious neglect or abuse had been documented," it said.
The demonstration came months after two Indian children, who were taken away from their parents on grounds of "emotional disconnect", returned to India after being kept in foster care for almost a year.