Relatives of Yemenis killed in a US drone attack are launching a court case today against the German government, in a landmark suit which could impede the CIA air strike program and impact international governments participating in the war on terror.

Faisal bin Ali Jaber and other members of his family will ask the German government to prevent the country from facilitating further drone strikes in Yemen, following allegations that the US Ramstein Air Base in the southwest of the country played a crucial role in a missile attack that killed five people in August 2012.

"Ramstein is unlawfully participating in a secret drone war in our country," said Jaber, whose brother-in-law and nephew and nephew were among those killed while the family gathered in an eastern Yemeni village for a wedding.

"I would like the German government to ultimately participate in a better, more productive, and less hurtful way of dealing with the problem of extremism that exists in Yemen, and for the court itself to hear how Ramstein airbase's role has a huge impact on our everyday lives in the village but also throughout Yemen."

Central to the case is the allegation, reported in a joint investigation between the Intercept website and Der Speigel magazine last April, that Ramstein plays a crucial role as a satellite station relaying communications between US operators in Nevada and drones in the Middle East. The US has permission to operate its site on German territory, but only if nothing done there violates German law — and some claim the US drone strikes constitute war crimes.

If successful, the case could set a precedent for other international governments that participate in the global war on terror to be challenged in court, and leave the US having to find a new location for the alleged command center.

The claim filed by lawyers from human rights group Reprieve and the European Center for Constitutional and Human Rights (ECCHR) in October 2014 argues that the German government is acting in breach of the country's constitution in allowing the US to use its Ramstein air base for illegal drone attacks abroad.

Jaber's brother-in-law Salim, a preacher, and nephew Waleed, a local police officer, were killed in the drone strike which hit the village of Khashamir on August 29, 2012. Salim had given a sermon criticizing al Qaeda the week before, says Jaber, and the day after the wedding a group of three unknown men drove to his mosque looking for him. He went to a nearby palm grove to talk to them with his son, Waleed, and seconds later all five were killed by a hail of missiles.

"It's very hard for me to go back to that day," he said. "The day before was the wedding of my son who is the first doctor to have graduated from the village. So it was a momentous occasion. The whole village was elated.

"Words don't begin to express what that day turned into when I was sat having dinner with my family and then heard the explosion of the first drone strike."

The strike sparked outrage in Yemen, and a Yemeni counterterrorism official called Jaber hours after to apologize for the mistake, he says. The following year, Jaber traveled to Washington on a trip sponsored by Reprieve and peace group Code Pink to hold the Obama administration to account over the strike. But he left without answers.

"I asked them at that time to review the drone program and its terrible effects," he said. "However, the drones continue to fly over our village at the same place and with the same terror, [which] makes us only more bitter and upset towards the US."

In July 2014 Jaber, 56, was called to Yemen's National Security Bureau — the Yemeni equivalent of the CIA. Al Jazeera reported that he was presented with a $100,000 bag of brand new dollar bills. No explanation was given for the source of the money; however Jaber and his lawyers believe it came from the US.

"A bag of freshly printed $100 bills is very clearly from the US," said Jaber. "The Yemeni intelligence services themselves do not pay compensation in this form.

"It leaves us with a feeling that the US, rather than recognizing us as humans and sending us an apology, deals with us by throwing money away and saying that's enough to keep quiet."

Jaber initially refused the money; however, he later handed it over to a committee formed by the victims' families to pursue justice and compensation.

"Until the US deals with the case in an appropriate manner the families will not benefit from that money," said Jaber.

Kat Craig, Reprieve's legal director and one of Jaber's lawyers, told VICE News: "The US's illegal drone program has been operating in the shadows, without any judicial or public scrutiny, since its inception. As a result, there is no chance for accountability, or avenue for redress, for innocent people whose lives have been devastated by US drone strikes.

"Germany, like every US ally that helps facilitate drone strikes, is partly responsible for the devastation they cause. This hearing is a huge step in turning the spotlight on their role."

Germany's Foreign Office did not respond to a request for comment from VICE News.