Ethiopian government forces "executed" three employees of medical charity Médecins Sans Frontières (MSF) while they were on a humanitarian mission in Ethiopia's war-hit northern Tigray region four years ago, a senior MSF official has told the BBC.

Raquel Ayora's comments came as MSF released its findings on what it called the "intentional and targeted" killing of the three - a Spanish national and two Ethiopians - at the height of the now-ended conflict in Tigray.

"They were executed," said Ms Ayora, MSF Spain's general director. "They were facing their attackers [and] were shot at very close range… several times."

The BBC has asked the Ethiopian government for a response to the allegation.

MSF said it was releasing its findings as the government had failed to provide a "credible account" of the deaths despite 20 face-to-face meetings over the last four years.

Thirty-five-year-old Spaniard María Hernández Matas, along with 32-year-old Yohannes Halefom Reda and 31-year-old Tedros Gebremariam, were killed on 24 June 2021 while travelling in central Tigray to assess medical needs.

"They were very professional and passionate," Ms Ayora told the BBC.

She added that the three were fully identifiable in MSF vests and their vehicle had the charity's flag and logos on either side when they were shot.

"So, they [Ethiopian troops] knew that they were killing humanitarian aid workers," she said, adding that the team's travel route had also been shared in advance with fighting groups.

The Tigray conflict broke out in 2020 following a massive fall-out between the regional and federal governments, with neighbouring Eritrea entering the war on the side of the Ethiopian National Defence Force (ENDF).

The conflict ended two years later following a peace deal brokered by the African Union (AU). Its envoy, former Nigerian President Olusegun Obasanjo, put the number of people who died in the conflict at around 600,000.

Researchers said the deaths were caused by fighting, starvation and a lack of health care.

The killings took place at a time when the conflict was intensifying, and Ethiopian and Eritrean troops were becoming increasingly hostile towards aid workers in the region, MSF said in its report.

Ms Matas had been working in Tigray since before the war and "was very much loved" by people in the region, Ms Ayora said.

Her death has been particularly devastating for her mother as she was her only child, the MSF official added.

Mr Tedros was killed soon after his wife had given birth to a baby girl. His widow named the baby Maria, after her father's killed Spanish colleague, Mr Ayora said.

The bodies of Ms Matas and Mr Yohannes were found between 100m (300ft) and 400m from the wreckage of their vehicle.

The body of Mr Tedros, the driver, was found by the vehicle."In line with MSF travel policy, the driver stays close to the vehicle", Ms Ayora said.

The vehicle was shot at multiple times and burned on the main road from the town of Abi Adi to Yech'illa, Ms Ayora said.

Ms Matas and Mr Yohannes were walking when they were shot, she said, adding: "We don't know if they were called for interrogation or they decided to engage with the soldiers."

MSF said it had relied on satellite images, witnesses and publicly available information on the Ethiopian military's movements at the time of the killings to draw its conclusions.

Its investigation placed Ethiopian troops at the "precise location" where the killings occurred, the charity added.

MSF's report quoted witnesses as saying they overhead an officer informing the local commander of an approaching white car and the commander giving an order to shoot.

Moments later, the commander was allegedly informed that the soldiers had tried to shoot but that the car had turned towards Abi Adi and stopped, at which point the commander gave the order to "go and catch them" and "remove them", the report alleged.

Ms Ayora told the BBC that officials from Ethiopia's Ministry of Justice had verbally informed MSF in mid-2022 that their preliminary investigation showed that government troops were not at the scene of the killing.

However, the officials refused to give this in writing, and the charity kept engaging with the government in order to end "impunity" at a time when an increasing number of aid workers were being killed in conflicts around the world, Ms Ayora said.