MEXICO CITY — Dozens of Roman Catholic priests and hundreds of parishioners marched through the southern Mexico city of Ciudad Altamirano on Wednesday to demand the release of a kidnapped priest and protest a series of kidnappings, killings and robberies of priests.

The marchers were led by Bishop Maximino Martinez and about 30 white-robed priests. They called for the release of the Rev. Gregorio Lopez Gorostieta, who apparently was kidnapped from a seminary on Monday.

“Enough Already!” and “Return Father Gregorio!” read banners carried by the marchers, who sang hymns as they marched to the city’s cathedral.

Lopez Gorostieta’s pickup truck was found abandoned, and the church has filed a crime report with police, but the motive remains unclear.

“We haven’t received any demand for ransom,” said Martinez, who noted his diocese “has suffered a lot” from the drug cartel violence that has made the hotlands region of southern Guerrero state one of the most dangerous in all of Mexico.

At least two priests have been killed in Guerrero state this year and several others have been abducted, robbed or wounded in robbery attempts.