Two Afghan brothers, both younger than 10, died this week after eating poisonous mushrooms while at a migrant center in Poland, BBC reports. Several members of the family ate the mushrooms on Aug. 24, with the brothers and a female member taken to the hospital for liver failure two days later. The three were treated for more than a week, with the girl, 17, recovering and leaving the hospital. However, the younger brother, 5, died Thursday after the Warsaw Children’s Memorial Health Centre could not arrange a brain transplant. The older brother, 6, died Friday.

The three were staying in a migrant center located in a forest outside Warsaw. They were among more than 1,000 Afghan refugees evacuated by the Polish military. After conflicting reports on why the family ate the mushrooms, police have launched an investigation.