NEWTOWN, Conn. - President Barack Obama has arrived in Newtown, Conn., to console families, thank first responders and speak at a vigil in memory of the 26 teachers and schoolchildren killed during a shooting spree at an elementary school Friday.

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This is the fourth trip of Obama's presidency to a grieving city in the aftermath of a mass shooting.

In his remarks, Obama will be addressing not only the residents of Newtown, but also a stunned nation. A White House official said Obama is the primary author of his speech and edited his remarks on the flight to Connecticut with White House speechwriter Cody Keenan.

Keenan helped Obama write his speech last year following the shootings in Tucson, Ariz., that killed six and wounded 13, including Rep. Gabby Giffords.

Twenty-six people, including 20 children, were killed when a man identified by authorities as Adam Lanza opened fire inside Sandy Hook Elementary school.

Hours after the shooting, a tearful Obama said he grieved first as a father. In those remarks and later in his Saturday radio address, Obama called for "meaningful action" to prevent such shootings, but did not say what it should be.

The president had planned to travel to Maine on Wednesday for an event promoting his positions in "fiscal cliff" negotiations, but the White House canceled that trip because of the shooting.