Organizers of the beatification of slain Salvadoran Archbishop Óscar Romero say they expect 200,000 to 260,000 to attend the May 23 event in El Salvador.

Archbishop Romero was fatally shot March 24, 1980, as he celebrated Mass. Often invoking the Gospel, he called for a stop to the violence and killing of civilians during the country’s civil war. More than 70,000 died in the conflict, which lasted from 1979 until 1992.

In February, Vatican officials said Archbishop Romero was killed “in hatred of the faith” and officially declared him a martyr.

The beatification ceremony will be at 10 a.m. local time at the Plaza Divino Salvador del Mundo (or Divine Savior of the World Plaza) in the bustling city center of the country’s capital, San Salvador.

The altar will have a relic, part of the shirt Archbishop Romero wore when he was fatally shot and which subsequently soaked up some of the martyr’s blood, officials said. The stage also will have a large image of Our Lady of Peace, the patroness of El Salvador. Organizers said they have arranged a VIP area for the poor, for peasants, for the country’s indigenous people — all those Archbishop Romero favored.

Televisión Católica de El Salvador, the country’s Catholic TV station, will livestream the ceremony at http://tvcaelsalvador.org. Catholic News Service will tweet live here at 8 a.m. Eastern time.

Organizers say they expect 200 bishops, 1,200 priests and six cardinals to attend. They will wear red vestments, signifying martyrdom, with Archbishop Romero’s episcopal motto: “sentir con la iglesia,” or “feel with the church,” also translated as “to think with the church.”