There have been calls to stop detaining children at the site
Two charities have expressed concern over a protest over medical care at an immigration centre in Bedfordshire.
Twenty people have been refusing meals at the Yarl's Wood centre since Monday.
A UK Border Agency spokesman said a number of detainees had been taken to different detention centres for "disrupting" normal operations.
Lisa Nandy, of The Children's Society, and Amanda Shah, from Bail for Immigration Detainees expressed fears for the welfare of the children there.
Impact on children
A joint statement said: "We are very concerned about the reports we have received from detainees in Yarl's Wood Immigration Removal Centre that families have been refusing food and sleeping in the corridors in protest at their treatment.
"We have also been told by one detainee that families were forcibly removed from the family wing in front of their children. We are particularly concerned at the impact this could have on the children in the wing.
"We have asked the UK Border Agency to intervene with some urgency to end this situation and ensure that all families are together, safe, that their needs are met and their concerns are taken seriously."
The protest at Yarl's Wood began on Monday and on Wednesday a number of detainees were separated off for "disrupting the normal operation" of the site, the UK Border Agency said.
Food from shop
The protest centres around claims that health care is "sub-standard".
A UK Border Agency spokesman said: "A handful of detainees who claimed they were refusing food have been eating from the centre shop."
Melchior Singo, 39, of Malawi, who is being held at the centre, said detainees had bought food from the shop for their children rather than themselves.
Mr Singo said his nine-year-old daughter Olger was referred to an orthodontist before they were held at the centre, but has since been denied further treatment.
The Home Office said 24-hour health care was available at the site.
The detainees are also protesting at children being held at the centre.
Yarl's Wood has 121 family beds, along with 284 single female beds, and a healthcare centre on site with a small in-patient ward, according to the UKBA.