A sociologist and former university administrator has been named governor of Guerrero, a state in southern Mexico that has been rocked by protests over the disappearance of 43 college students who were last seen in police custody.

Rogelio Ortega Martinez was chosen by the state's congress on Sunday to replace Angel Aguirre Rivero, who stepped down last week.

The 59-year-old Ortega previously was secretary-general of Guerrero's state public university. Ortega is a former social activist and the son of a rural schoolteacher. He has close ties to the state's ruling Democratic Revolution Party.

Authorities have yet to locate the students from a rural teachers college who disappeared after a Sept. 26 confrontation with police in the city of Iguala. The disappearances have sparked nationwide protests.