Pope Francis issued an invitation to mark today as a day of prayer and fasting for peace. He will lead a Vigil of prayer in Saint Peter's Square this evening. Here is the schedule (Rome time):

5:45: Priests will hear confessions under the colonnade of Saint Peter’s Square.
6:30: Pope Francis’ appeal for peace will be read aloud.
7:00: The Pope begins the prayer service as Veni Creator Spiritus is sung. The icon Salus Populi Romani will then be processed into the Square, carried by four Swiss Guards.
Pope Francis will then lead the recitation of the Rosary, followed by a meditation.
After a period of silent meditation, the Holy Father will then preside over Eucharistic Adoration, during which there will be readings from Scripture and responsorial prayers.
Following the guided period of Adoration, there will be the recitation of the Office of Readings from the Liturgy of the Hours.
10:15: A period of silent prayer will be held before the vigil concludes with Benediction.

I believe that EWTN will broadcast the Vigil beginning at 1:00 p.m. Eastern time.