The search for 43 Mexican college students continues after three months, and now officials are looking for kidnapped clergyman as well.

Dozens of Catholic priests and hundreds of supporters marched through Ciudad Altamirano on Wednesday in protest of the kidnappings – and robberies and killings – that have plagued Guerrero state.

The male students attended Raúl Isidro Burgos Rural Teachers' College of Ayotzinapa, and were on several buses heading to a political protest on September 26. While in Iguala, Guerrero, the students clashed with police, and three students were killed. Authorities believe the remaining students were turned over to a gang and murdered. The remains of one of the students, 19-year-old Alexander Mora Venancio, were identified earlier this month.

About 100 miles west of where the students disappeared, protesters took to the streets on Christmas Eve to demand the release of Rev Gregorio López Gorostieta. The priest's car was found abandoned, and Gorostieta has been missing since Monday, reports Fox News.

"We haven't received any demand for ransom," Bishop Maximino Martínez said. Marchers carried signs reading "Return Father Gregorio!" and "Enough Already!" as they marched to a local cathedral.

In September, the body of Rev Ascension Acuna Osorio was found in in the Balsas River, with no explanation given for his death. Earlier this year, a Ugandan priest visiting Mexico, RevJohn Ssenyondo, was kidnapped and killed after officiating Mass. His body was discovered last month during the search for the missing students.

There have also been drive-by shootings targeting priests, threats of violence, and other terrorising acts. The clergymen believe they are being attacked for condemning the rampant violence in the state, which has been attributed to the Guerreros Unidos drug cartel.

Mexican Federal Police Chief Enrique Francisco Galindo announced Tuesday that the search for the students is their top priority, and will continue. At least 75 people have been arrested in connection with the missing students, including Iguala Mayor Jose Luis Abarca.