For decades, they often wait for a sign of life from their missing daughters and sons, and the police rarely investigate: In Mexico, cartels and gangs have kidnapped thousands of people in recent years. More than 40,000 people are currently missing. Many are murdered and buried in mass graves. The police and military are also behind kidnappings and killings.

Family members use tools such as sticks, pimples, and spades to hunt down the disappeared, and in some states, mothers and grandmothers use drones to search for traces of their lost children or their remains.

Drones would be an "absolute paradigm shift" in the search for disappearances, says Mexican journalist Oscar Balmen DER SPIEGEL. "Seekers are almost all mothers and grandmothers between the ages of 50 and 70 who have to search large areas such as hills and plains, but because of their age can only cover a very small area, drones allow them to reach even higher and inaccessible areas . "

The drone flights would also protect the health of women - many were already in the attempt to reach hard to reach areas, and had injured. Balmen has researched for the radio program "Primera Emisión de MVS con Luis Cardenas", as the Disappeared Initiative "Fuerzas Unidas Por Nuestros Desaparecidos / as" in the state of Nuevo León uses drones.

Although the state of northeastern Mexico, with its high economic performance and governmental capacity within Mexico, is in a state of emergency, it is one of the four states with the highest number of missing persons in the country, according to a study by the Observatory for Disappeared and Impunity "Observator sobre Desaparición e Impunidad ". Cartels are fighting for the lucrative market, and the presence of military leaders who themselves commit human rights crimes and are themselves on the payrolls of criminals aggravates the conflicts.

According to Alberto Xicotencatl, human rights expert and head of the Casa del Migrante Saltillo, SPIEGEL, the government has introduced a disappearance law and a national search commission under pressure from family members. But the process continues. "The relatives continue to demand that the disappeared be found alive, but they also know that it is likely that they are no longer alive, the more time passes, so they try to find secret graves and with the help of technology remains to find, "says Xicotencatl.

Search for Narco Houses

Per drone, whose battery lasts about half an hour, the mothers and grandmothers can discover suspicious houses of criminal groups from the air, take photos and record the exact geographical coordinates. "The houses of criminals in Nuevo León, where they abduct their victims and murder them, have a very specific style," says Balmen. So the women would know what to look out for in their drone flights: abandoned buildings hidden in hills that are connected by roads.

Of which 2015, al menos tres asociaciones de familiares con desaparecidos en Baja California, Veracruz y recientemente Nuevo León, se han capacitado en el uso de drones para encontrar a sus seres queridos. pic.twitter.com/LsBojR98Qf

- Oscar Balmen (@ oscarbalmen) April 9, 2019

Many of the houses are also near a creek or river, usually they have no real roofs, but are, for example, improvised covered with wood. "When these characteristics come together, the relatives know that they have come to a death house of the cartels, and it is very likely that the remains of a loved one will be found around the houses," said Balmen.

The drones can also detect the temperature of the earth via a drone and detect areas that are not overgrown or where the ground seems looser than usual - an indication of grave sites. On the high-resolution images, they even recognize the tire tracks left by the cars of the kidnappers and murderers.

Remains of dead

However, in order to deal with their suspicions and the evidence they have collected from the air, the drone pilots are dependent on the law enforcement authorities - together with the local police and prosecutors, they then seek out the suspicious places. "The majority of mothers have taken forensic courses, they know how to guide the authorities," says Oscar Balmen. "It would be dangerous for them to visit the places without police escort, because they could be attacked by the criminal groups, or else the forensic evidence could not be used for investigation."

Family-run Disappeared Organizations in at least three states in Mexico now use drones. In Nuevo León, the mothers and grandmothers have saved money for their US-imported "Phantom 3" drone from DJI through charity events.

In view of the complex task, it is more of a "basic drone," says Oscar Balmen. However, the women make the most of the resources that are available to them: According to Balmen, they have now become drone experts who also program flight routes themselves, which are then automatically flown off. With their search missions they have been able to find 1,600 bones, so Balmen.

The findings help the relatives of the identified dead at least a little further - because they have certainty. "It's emotionally exhausting to spend your entire life searching for the disappeared and preventing it from focusing on anything else," says human rights expert Alberto Xicotencatl.

The state also buys drones

Some authorities and government agencies in Mexico also use drones for major search missions, such as the states of Baja California and Guerrero. The local government of Nuevo León has also bought its own drone - the purchase of professional unmanned aerial vehicle, which should be used to search and localization of the disappeared, was controversial due to the high expenditure. 54 million pesos cost the aircraft the state, more than 250,000 euros.

According to a video released by the governor of Nuevo León on Twitter, the about three-meter-long drone "UAV MX1" should be able to stay in the air between seven and twelve hours and cover 100 to 200 kilometers - at least in theory.

Ayer entregamos a Fuerza Civil una aeronave no tripulada para que los apoye en la seguridad del estado, échenle un ojo al video y ayúdenme a darle RT para que to toos. pic.twitter.com/TymmK8LWwm

- JAIME RDZ EL BRONCO (@JaimeRdzNL) 20 March 2019

Because still in Nuevo León are the mothers who have to help out the state - with their entry-level drone. "Despite the millions spent, the authorities do not use their drone because it is not functional," says Balmen. "Not only do the mothers do the work the authorities should do, they even lend them their drones, and the mothers teach the state officials how to fly them."