El Salvador's President Salvador Sanchez Ceren participates in a graduation ceremony at the Command of Doctrine and Military Education in San Salvador, El Salvador, July 11, 2018. REUTERS/Jose Cabezas

SAN SALVADOR (Reuters) - El Salvador’s government said on Wednesday a Supreme Court ruling that seeks to compel testimony from the president over the disappearance of a diplomat nearly 30 years ago in the run-up to the country’s bloody civil war was a political attack.

The court said on Tuesday that President Salvador Sanchez Ceren, a 74-year-old former guerrilla leader, must testify over the kidnapping of a South African diplomat in 1979.

The ruling came after the family of then-South African Ambassador Archibald Gardner Dunn filed a lawsuit blaming the Liberation People’s Forces (FPL) ex-guerrilla group for his disappearance on Nov. 28, 1979.

“The president did not belong to the leadership of the FPL that year, and was a labor leader for teachers. This ruling has the political aim of hurting the president’s image,” presidential spokesman Roberto Lorenzana said in a brief statement.

According to the lawsuit, the FPL never disclosed Gardner Dunn’s whereabouts even though a ransom of $2 million was paid for his release.

Salvadoran media reported in October 1980 that Gardner Dunn was executed by the FPL. The diplomat’s family said in the lawsuit it had no solid information on his fate.

El Salvador’s 1980-1992 civil war pitted the leftist Farabundo Marti National Liberation Front (FMLN) against the U.S.-backed Salvadoran army. The FMLN was formed from a merger of several dissident leftist groups, including the FPL.

The war killed some 75,000 people and left 8,000 missing.