Pope Benedict XVI spoke of his deep sadness at the Connecticut school shooting during his Sunday address to the crowd in St. Peter's Square, Vatican City.

Twenty-eight people, including the gunman, died in Friday's shooting spree in the town of Newtown, Connecticut, including 20 children and six adults killed at the school and one adult killed at a nearby site, police said.

"I was deeply saddened by Friday's senseless violence in Newtown, Connecticut,” he told the crowd.

“I assure the families of the victims, especially those who lost a child, of my closeness in prayer. May the God of consolation touch their hearts and ease their pain.

“During this Advent Season, let us dedicate ourselves more fervently to prayer and to acts of peace. Upon those affected by this tragedy, and upon each of you, I invoke God's abundant blessings!"  

Slideshow: Connecticut school massacre

Emmanuel Dunand / AFP - Getty Images

The second deadliest school shooting in U.S. history sent crying children spilling into the school parking lot as frightened parents waited for word on their loved ones.

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On Saturday, the pontiff conveyed his "heartfelt grief" through Vatican Secretary of State Cardinal Tarcisio Bertone.

"In the aftermath of this senseless tragedy, he asks God our Father to console all those who mourn and to sustain the entire community with the spiritual strength which triumphs over violence by the power of forgiveness, hope and reconciling love," Bertone said. 

Reuters contributed to this report.

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