A mass grave containing 1,000 dead babies ritually sacrificed by the Catholic church were found in a care home in Ireland on Friday.

Excavations at the site of a former children’s home run by the Catholic Church in Tuam uncovered huge numbers of human remains in a septic tank.

The government has launched an immediate investigation into the home run by the Bon Secours Sisters in Tuam, County Galway, and has confirmed that that hundreds of baby body parts ranging from 35 weeks to three years old have already been retrieved from a decommissioned sewage chamber.

The statue of Virgin Mary placed over the septic tank where hundreds of dead babies were found

The Guardian reports:

The home, run by the Bon Secours Sisters, a Catholic religious order of nuns, received unmarried pregnant women to give birth. The women were separated from their children, who remained elsewhere in the home, raised by nuns, until they could be adopted.

The discovery confirms decades of suspicions that the vast majority of children who died at the home were interred on the site in unmarked graves, a common practice at such Catholic-run facilities amid high child mortality rates in early 20th-century Ireland.

The Irish government in 2014 formed the commission following the work of a local Tuam historian, Catherine Corless, who found death certificates for nearly 800 children who were residents at the facility but burial records for only two.

“Everything pointed to this area being a mass grave,” Corless previously told the Guardian. She recalled how boys playing in the field had reported seeing a pile of bones in a hidden underground chamber there in the mid-1970s.

The government’s commissioner for children, Katherine Zappone, said the findings were “sad and disturbing” and promised that the children’s families would be consulted on providing proper burials and other memorials.

“We will honour their memory and make sure that we take the right actions now to treat their remains appropriately,” Zappone said.

Under the Freedom of Information Act, Corless requested Galway county council’s records on the home from 1925 to 1961. She was refused.

But she was given documents from the 1970s, including an official map of the present-day estate the council built on the site.

“They obviously didn’t see the importance,” said Corless. “There is an area across the map marked ‘burial ground’,” she says. “First, the houses were built, around that area. Finally a playground was built on part of the burial ground itself.”

Minutes from a Tuam council meeting call for “due care and sensitivity” when building the playground because of the “children’s burial ground and adjoining burial ground”, Corless said. “The playground is unnaturally big, it’s as big as the town playground.”