MADRID (AP) — Spain’s National Court has extended the detention period for a former Salvadoran colonel who was allegedly involved in the massacre of five Spanish priests in El Salvador in 1989.

The court said Thursday that Inocente Orlando Montano could be kept in jail for another two years while his trial is prepared. It cited the seriousness of the charges and the risk of him fleeing if released.

The United States extradited Montano to Spain in 2017 to face charges of terrorist murder and crimes against humanity in the deaths of the priests. Montano served as vice minister for public security in the 1980s during El Salvador’s civil war.

Father Ignacio Ellacuria and the other priests were helping organize peace talks to end the war. Their housekeeper and her daughter were also killed.