The 19 interpreters wrote to the German government on 7 August asking for protection as the jihadist groups that operate in northern Mali regard those who work with the UN as traitors.
"The terrorists have been openly saying that any person working for international forces is considered an enemy," a translator for the UN's German military contingent, whose name has been withheld for safety reasons, told the BBC.
A few weeks after the translators sent their letter, photos appeared online of their friend Hachimi Dicko being killed by gunmen from the Islamic State (IS) group.
The 32-year-old Malian had worked for a sub-contractor at Camp Castor, the base that is operated by German UN soldiers in Gao, northern Mali's most populous city.
All the translators knew Mr Dicko well. He had been a laundry supervisor at the camp, working for Ecolog - although a source close to his family says when he was captured by IS gunmen in June his contract had come to an end.
He had started a job as a clothing courier and had been travelling on a lorry from Niamey, the capital of neighbouring Niger, to Gao when it was ambushed.
Those travelling with him say he was singled out by the gunmen because of the military-style boots he was wearing. They initially demanded a ransom. The lorry driver got in contact with the family at the militants' request.
But as negotiations were happening by the side of the road, the IS gunmen started going through Mr Dicko's phone and found photos of him standing next to German UN soldiers.
Those pictures sealed his fate. The jihadists said they were no longer interested in a ransom. They abducted him, calling him a spy and an enemy accomplice. It is not clear when he was killed, but the images of his brutal murder were circulated online two months later.
The BBC has asked Ecolog to confirm that Mr Dicko was an employee but has not received a response.
The translators say Mr Dicko's murder shows the real danger they are in as they are known across the vast desert region.
"When we go to the field, our job is to go out to collect information for the forces. I have gone to many villages, and they call me 'kufur' (infidel). They tell me to my face that any person who works for infidels is also an infidel," said the translator who has worked for the UN for seven years.
He says even if he recites the shahada - a declaration of a Muslim's faith - some despise him for "taking the infidel's money".
"They know who we are, our faces are out there, they are just waiting for the international forces to leave the country for them to attack," he says.
"We work with the military, everywhere they go, we are there because we are their mouth, and a lot of bad people consider us spies.
"I've told my bosses, [about the threats] but they've done nothing. Now Germany is leaving soon but they haven't planned anything for us," he says.
In the translators' letter they state: "Your departure will create a great security void, especially for the interpreters who have played a very sensitive role since the start of the mission... We fear the risk of reprisals after the withdrawal of this mission."
A spokesperson for the German foreign ministry told the BBC that there are protective measures to ensure the safety of local staff should a crisis happen, including financial and logistical support to move them to safer areas or countries within the region.
Yet the German Defence Joint Forces Operations Command in Mali says it is continuously assessing the security situation and can find no reliable evidence of a systematic or individual threat to local employees.
"It became clear that all of the concerns and fears raised by local employees remained unspecific, vague and abstract. In particular, even when asked, the local employees were unable to provide any evidence of a risk due to their work," it said in a statement to the BBC.
German soldiers have not yet withdrawn from Camp Castor, but must do so by 31 December when the UN mission's mandate officially ends - at the request of the military government that took power in a coup in 2020.
Since some UN contingents began pulling out a few months ago, there has been an upsurge in violence in the north.
According to areport by the UN Security Council, armed groups are capitalising on the security vacuum and IS has almost doubled the areas it controls in less than a year.
The UN mission, known as Minusma, has operated in Mali since 2013 - deploying a year after Islamist groups and their Tuareg rebel allies seized the north of the country. Together with French troops, they regained control of the main cities but the jihadists have continued their insurgency from desert outposts.
Minusma is made up of military personnel from nearly 60 countries, with Germany, along with Bangladesh, Chad, Egypt and Senegal, among the main contributors.
UN agreements with these nations do not offer protection to Malians employed by them on temporary contracts - something that the group Interpreters in Conflict Zones at the International Association of Conference Interpreters (AIIC) has been campaigning to change since 2009.
About 900 Malians have been employed to work with Minusma as translators, drivers and other support roles across the 12 UN bases nationwide.
"We are worried that with the withdrawal of troops in Mali, the same thing will happen in Mali as it did in Afghanistan," Linda Fitchett, AIIC's project leader, told the BBC.
"If we cannot get the UN to adopt a protective text, who is going to protect these interpreters?"
After the withdrawal of US forces in Afghanistan in 2021, thousands of translators were left behind. Some have been executed by the Taliban and many more are in hiding.
Last year, AIIC, together with 21 other organisations, wrote to German ministers calling for the extraction of the Malian translators and their families "prior to full withdrawal".
Another translator for the Germans, who requested anonymity, told the BBC: "We saw what happened in Afghanistan after the departure of the Americans and it can happen here."
He questioned what further evidence German officials needed to understand their danger when he had opted to live inside the camp since starting work for them seven years ago.
"Do they want one of us to be kidnapped and killed? If there were no security concerns, would we be sleeping in the German camp?"
When taking part in a German mission that involved seizing weapons from jihadist groups, he said one person warned him: "I know who you are."
Even moving to the south of the country, which is considered safer, would not be enough, he warned.
"The jihadists are everywhere. We are OK to go to another African country, they don't have to take us to Germany."
More on Mali's insurgency:
Translators who work for German peacekeepers in Mali have told the BBC they fear for their lives as the UN mission winds up its mission in the West African country.