MEXICO CITY — They look in Mexico’s loneliest corners, on hillsides and in woods and across empty fields. They look for the places others might have forgotten, in tight ravines and trash dumps and vacant lots, poking sticks into the soil and sniffing them for the scent of death.

The search for Mexico’s disappeared — people who have been killed but whose bodies have not been found — is one of the saddest rituals of the country’s decade-long drug war. Across Mexico, mothers and fathers, husbands and wives, have banded together to search for their missing loved ones. These men and woman — one such group in the Pacific Coast state of Sinaloa is known as Seekers for Peace — often do this on their own because the government has failed to find their loved ones.

Mexico’s government says that more than 30,000 people are missing. But this number is notoriously unreliable and subject to change. Last month, authorities in Veracruz state found a new mass grave with at least 174 bodies. In the most high-profile disappearance in recent years, 43 students of a teachers college went missing in the state of Guerrero in 2014. They have still not been found.

In these images, photographer Alejandro Cegarra followed residents from Sinaloa, one of the centers of drug production and cartel operations, as they searched for missing relatives in September. Since forming in 2014, citizen groups have found more than 200 dead but have a list of more than 700 who remain missing. Some disappeared within the month; others have been gone for years.

Each Wednesday and Sunday, mothers and wives spend hours searching rural land outside Los Mochis for clandestine graves using metal rods to probe the earth for signs of decomposed bodies. They hold marches to protest the violence and to ask for more government support. And they hold funerals when they find unmarked remains.

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