The anguished families of 43 missing Mexican students knocked on doors of brick homes Wednesday, handing out pictures of the aspiring teachers who vanished after a deadly police shooting at the weekend.
Some relatives waded through fields of chest-high wildflowers, while others, backed by scores of marines, soldiers and state police, looked in gullies, empty lots and villages around the southern town of Iguala, where the trainee teachers were last seen.
Witnesses saw many of the students being whisked away in municipal police cars after officers fired on their buses as they headed home late Friday in the crime-plague state of Guerrero.
Authorities suspect the officers have links to drug gangs, raising fears over the fate of the 43 in a country where 80,000 people have died in drug violence and 22,000 have gone missing since 2006.
"The search is taking place in places that people know as being high-risk because organized crime dominates these places," said Manuel Olivares, coordinator of the Guerrerense Network of Human Rights Organizations.
While the families remain hopeful their loved ones will turn up alive, he said they are looking in places that gangs use to bury bodies.
But the nine relatives knocking on doors around Iguala are not giving up, breaking up in groups of three and accompanied by 20 troops and police each.
"Good afternoon, we are looking for relatives who disappeared last weekend. We hope you can help us with any information," Meliton Ortega, a corn farmer looking for his 17-year-old nephew, said to two pig farmers.
"We haven't heard anything aside from what's in the news," Epifanio Romualdo, 53, replied as he took a flyer, promising to call the number on it if he hears anything.
On they went, door to door, sweating heavily as they traipsed up sun-soaked hills, hearing the same answer everwhere: "Nada" (Nothing). In one house, a polka-like northern corrido beat rang out but nobody responded to their calls of "hola!"
"We will search until they reappear," said Epifanio Alvarez, a farmer looking for his 19-year-old son.
- 'We want them back' -
State prosecutors detained 22 municipal officers over charges that they fired on three buses carrying the students, killing three of them.
Officers are also accused of shooting at a bus carrying a third-division football club and a taxi on the outskirts of Iguala, killing three people. Authorities say a gang may also have been involved.
The students, from the Ayotzinapa teacher training college near the state capital Chilpancingo, say they went to Iguala on Friday to raise funds for their studies.
While Guerrero's radical teachers-in-training have held protests against reforms and work conditions in the past, they denied they demonstrated in Iguala.
They admit seizing buses to return home, a common practice among the students, who say they have no choice because of a lack of government aid.
A student who survived told AFP that he saw police take away 30 to 40 students in patrol cars after the shootings.
Prosecutors say street surveillance cameras showed patrol cars carrying civilians.
Some families fear the students could now be in the hands of a gang.
"We haven't rested since we started searching last weekend," Ortega said. "They were taken away alive, we want them back alive."