A man whose father was killed in a U.S. drone strike in Somalia is seeking to hold Germany accountable for allowing the United States to use its territory for military bases that play a key role in overseas airstrikes.

In legal complaints filed in Germany last week, a Somali man, whose name was given only as “C.D.,” described his father, “A.B.,” as a herdsman who raised goats and camels in southern Somalia, not far off the coast of the Indian Ocean.

According to his son’s testimony, A.B. left home on the morning of February 24, 2012, to graze his livestock — but that night, several of his camels came home without him. The next day C.D. found his father’s body severed in two, near a burnt-out car and several dead camels.

The strike that killed A.B. was apparently aimed at Mohamed Sakr, a London-born alleged member of the Somali jihadist group al Shabaab, who had his British citizenship stripped from him in 2010. By some accounts several other unidentified people also died.

C.D.’s lawyers argue that the killing of A.B. and Sakr amount to murder under German law, and that German officials may be liable because of their cooperation with American forces. The complaint asks for an investigation by the public prosecutor in the district that hosts Ramstein, the enormous U.S. airbase that serves as a satellite relay station connecting drone pilots in the United States with their aircraft flying over Yemen, Somalia, Pakistan, and Afghanistan.

The complaint cites reporting by The Intercept, Der Spiegel, and others detailing Ramstein’s critical logistical role in the U.S. drone war. It also points to the fact that U.S. Africa Command, or Africom, headquartered in Stuttgart, oversees operations in Somalia like the one that killed A.B.

The case was filed by German lawyers backed by the U.S.-based Open Society Justice Initiative. They also lodged a civil complaint with a court in Cologne, arguing that Germany violated NATO agreements and its constitution by allowing the U.S. to use Stuttgart and Ramstein for drone strikes in Somalia.

German and U.S. officials have previously sidestepped questions about Ramstein’s significance, saying that drones are not directly flown or controlled from the base. Neither the Pentagon nor the German Embassy in the District of Columbia responded to requests for comment on C.D.’s case.

This spring, the court in Cologne dismissed a lawsuit brought by the family of Yemeni drone victims who had also argued that Germany was complicit in U.S. drone strikes and bore responsibility for civilians harmed in them. In that case, the court decided that it did not have the authority to intervene in the terms of the Ramstein contract, and that the German government was “not obliged to prevent the United States from using the airbase in Ramstein for executing drone strikes.” (The human rights group behind that suit has appealed the decision.)

C.D.’s effort differs from the Yemeni case because it asks the court only to find that the German government violated the law in this particular strike, said Amrit Singh, legal officer at the Open Society Justice Initiative.

Singh and her German partners also believe they can persuasively argue that at the time of the strike, neither Germany nor the U.S. was in a traditional armed conflict in Somalia.

Compared to dozens of strikes in Yemen and hundreds in Pakistan, there have been a reported maximum of 19 U.S. drone strikes in Somalia since 2007, and detailed accounts of civilian harm are rare. Given Somalia’s instability there is very little media or other independent verification of strikes or their aftermath. According to news accounts compiled by the Bureau of Investigative Journalism, between 25 and 108 people have been killed, including up to five civilians.

A.B.’s death was first reported by German journalists in 2013. The son has chosen to remain anonymous out of concern for his personal safety, said Singh.

“In the face of governments that assert the unilateral authority to kill, a poor person like our client is rendered so powerless,” Singh said.