Watch live: Obama speaks at Newtown shooting vigil

A gunman opened fire on Friday at Sandy Hook Elementary School in Newtown, Conn. Twenty children were among the victims of the mass shooting.

President Obama traveled to Newtown on Sunday to talk to victims' families and emergency personnel. An interfaith vigil is being held tonight, and Obama is expected to speak. NBCNews.com has live coverage. Watch the vigil now on NBCNews.com.