Trump fired back, saying it is disgraceful for a religious leader to question a person's faith.
The pontiff used his time here to criticize Mexico's ruling class for failing to protect people from predatory criminal gangs and rampant corruption.
With the song "Las Golondrinas", folklore dancers and dozens of people waving handkerchiefs in farewell, Francis boarded the airplane.
Francis prayed for the thousands of migrants who have died trying to reach the U.S.
Next to a giant crucifix, he made the sign of the cross and blessed hundreds of people gathered a few yards away on the U.S. side.
Pope Francis won't step foot in El Paso on Wednesday, but his presence across the border in Ciudad Juárez was still being widely felt in the West Texas city.
The pontiff said that “God will judge those who enslave others” and that “capital flows should not determine the life of people”.
The pontiff urged the inmates of Cefereso No. 3 to help end the cycle of violence and crime and to forgive the society that failed to help them.
Alitalia said the plane's crew noticed the laser coming from the ground on Friday as the pope was coming in from Cuba.
Two arms reached out to grab him and the person would not let go, even after the pope lost hisbalance and his chest was pressing on the child’s head.