International medical charity, Médecins Sans Frontières (MSF) on Wednesday said that it has ceased aid operations in several parts of central and eastern Tigray.
MSF, also known as Doctors Without Borders, said it has suspended humanitarian operations in Abi-Adi, Axum, and Adigrat towns following the brutal killings of three of its staff late last month.
The three - Maria Hernandez, Yohannes Halefom Tedros Gebremariam Gebremichael - were found dead on June 24. They were killed while on a humanitarian mission in Abi-Adi. Ms Hernandez (emergency coordinator) was a Spanish national while Halefom (assistant coordinator) and Gebremichael (driver) were Ethiopians.
While MSF noted that it will continue to provide emergency assistance to people in need in other parts of Tigray, it demanded an investigation into the deaths.
"It has been almost two weeks since the murders of our colleagues. No one has claimed responsibility and the circumstances around their deaths remain unclear," says MSF operations director Teresa Sancristoval.
"This is why we are requesting an immediate investigation by relevant parties to establish the facts of the incident that resulted in their deaths and to provide us with a detailed account of what happened and who was responsible...At this terrible time, we have made the extremely painful but necessary decision to suspend our activities in several areas of Tigray."
She added that if MSF and other aid organisations are to continue working in Tigray and in other parts of the country, all parties to the conflict must provide assurances that this work can be carried out safely.
"Parties to the conflict must take responsibility for ensuring that an incident like the murder of our colleagues never happens again," she added.
The suspension of MSF's activities has created a huge gap in the provision of critical medical and humanitarian assistance for hundreds of thousands of people in need in central and eastern Tigray.
All parties to the conflict in Tigray have been accused of atrocities against civilians and various other human rights violations.