A Yemeni man is suing the German government for allegedly letting the United States use an air base in Germany for lethal drone strikes.

Faisal bin Ali Jaber claims his brother-in-law, Salim bin Ahmed Ali Jaber, and nephew, Waleed, were killed in a U.S. drone strike in August 2012.

Human rights group Reprieve, which along with the European Center for Constitutional Human Rights represents bin Ali Jaber, alleges the drone was controlled via the U.S. air base at Ramstein in southwestern Germany.

Reprieve's legal director, Kat Craig, told The Associated Press on Wednesday that there was sufficient evidence to prove Ramstein's role in the transmission of flight control data from pilots in the United States to drones in the Middle East.

Germany's Foreign Ministry declined to comment on the case.