Rev. Marcelo Pérez was shot dead by two gunmen when he was in his van, just after he had finished celebrating Mass, the state prosecutors' office said.

Gunmen in Mexico have shot dead a Catholic priest who was an outspoken advocate for indigenous rights and who had condemned the violence plaguing his community. Father Marcelo Pérez was killed after celebrating Mass in the southern state of Chiapas on Sunday, the prosecutor's office said.

Mexican authorities have arrested the alleged murderer of a Catholic priest and prominent human rights defender whose killing triggered international condemnation, officials announced Tuesday.

He served the Tzotzil Indigenous community for two decades and was known as a negotiator in conflicts in a mountainous region of Chiapas where crime, violence and land disputes are rife.