A former Mexican mayor and his wife accused of ordering the kidnapping of 43 missing college students have been detained in the nation’s capital, according to a spokesman for the federal police

Jose Luis Abarca, who was mayor in the town of Iguala when the students disappeared in September 2014, was apprehended in Mexico City by federal officers along with his wife, Maria de los Angeles Pineda, Jose Ramon Salinas said. Both Abarca and Pineda are suspects in the disappearances, Attorney General Jesus Murillo said. The detentions mark a milestone in a case that has sparked protests by tens of thousands, pushing President Enrique Pena Nieto to vow to bring the perpetrators to justice. Federal authorities investigating the disappearances say that the students were handed over by local police to a drug gang in Iguala after they tried to disrupt a public event held by Pineda. “If this helps clear up what happened to the students, it will help Pena Nieto’s government recover some of its lost prestige,” Jorge Chabat, a security analyst in Mexico City, said. “This case has exposed some of the big flaws in this country’s institutions.” Families of the students met with Pena Nieto recently, demanding results from an investigation that after five weeks has failed to determine whether those missing are dead or alive. Officials are in the process of identifying remains from mass graves in Iguala and a nearby town. The capture of Abarca and his wife “can contribute significant elements” to the investigation, Vidulfo Rosales, a lawyer representing parents of the missing students, said. “The parents are enduring great suffering, and are seeking any news, whatever it may be.” Public outrage over the Iguala case is undercutting Pena Nieto’s efforts to focus attention on an economic agenda, including the end of the state’s seven-decade oil monopoly. A drug war that has left about 70,000 dead in the past eight years has been brought back into the spotlight, with Pena Nieto or subordinates addressing the search for the students on national TV on an almost daily basis. The former Iguala mayor and his wife were detained in a house in Mexico City’s Iztapalapa borough and were taken for questioning by federal authorities. “It’s very important that the Mexican public see that that level of government impunity is being dealt with,” Duncan Wood, director of the Mexico Institute at the Woodrow Wilson International Center for Scholars in Washington, said. “What it doesn’t do is solve the underlying problem in Mexico, which is weak institutions.” Investigations into the disappearance of the students led federal authorities to take over security in 12 Guerrero towns recentl after uncovering alleged links between local police and organized crime. The police in Iguala, about 180 kilometers (112 miles) southwest of Mexico City, handed over the students from a teachers college to drug gang members, who then took them to an area where mass graves were found, Murillo said. Another grave was found in nearby Cocula, and police from both towns have been detained in the investigation. More than 50 people have been detained in the case, including local police and members of the Guerreros Unidos gang and its alleged leader Sidronio Casarrubias. The disappearances followed attacks on the students and others caught up in the violence on September 26 and 27, 2014 that left six people dead. Abarca took leave in September 2014 before he and his wife vanished, and he was stripped of his immunity from prosecution recently.