Morelia (Mexico): Pope Francis, who is usually calm and accommodating with his admirers, clearly lost his temper with a person who pulled on him so hard that he fell onto a child on a wheel chair.
Video footage showed that while the pope was walking at the edge of a crowd in an stadium, he stopped to greet children who were sitting.
Two arms reached out to grab him and the person would not let go, even after the pope lost his balance and his chest was pressing on the child's head.
Aides and security men stopped the pope from falling to the ground.
After he returned to an upright position, his face turned angry.
He looked at the person, raised his voice and said twice in Spanish: "Don't be selfish!"
It was not clear if the person who pulled the pope was a man or a woman.
Pope Francis begged young people in Mexico's gang-infested heartland on Tuesday to shun the lure of easy money and big cars offered by drug traffickers.
"It is a lie to believe that the only way to live, or to be young, is to entrust oneself to drug dealers or others who do nothing but sow destruction and death," he told young people at a stadium rally in Morelia, the capital of Michoacan.
More than 100,000 people have been killed in Mexico's drug war over the last decade as rival gangs fight over territory and smuggling routes to the United States.
Francis, the first Latin American pope, is traveling to some of the poorest and most violent corners of Mexico on a six-day trip to bring a message of hope to millions of marginalised people.
While appealing to the young to shun a life where fleeting happiness is found in easy money, fast cars and brand-name clothes, Francis also took a swipe on Tuesday at Mexican authorities for failing to provide opportunities for the young.
"It is hard to feel the wealth of a nation when there are no opportunities for dignified work, no possibilities for study or advancement, when you feel your rights are being trampled on, which then leads you to extreme situations," the pope told them.
There was tight security for the visit to Morelia, a picturesque city known for its Spanish colonial architecture, given scattered outbursts of violence in recent months.
It is Francis' first trip to Mexico as pontiff.
On Tuesday morning, the Argentine pontiff urged priests not to be resigned to evils around them like drug trafficking, and not to remain entrenched in their churches, but rather to head out to the front lines to help those suffering.
Before the rally with the young, Francis visited Morelia's 17th century baroque cathedral. Tens of thousands of people who could not enter his events lined the streets for a glimpse of the pope.
Before Francis entered another stadium in Morelia for a morning Mass, the crowd counted aloud to 43, a gesture to remember dozens of trainee teachers who were abducted and apparently massacred by a drug gang in league with corrupt police in 2014 in the neighboring state of Guerrero.