President Obama called Sunday for a “transformation” of the nation’s gun laws, saying last week’s deadly shooting at the Washington Navy Yard echoes too many other killings across the United States.

“Our tears are not enough,” Obama said during a memorial service for the victims and their families. “Our words and our prayers are not enough … We are going to have to change.”

Gun violence in America “ought to obsess us,” Obama said.

Acknowledging that a gun control package he proposed earlier this year has stalled in Congress, Obama said the change won’t come from Washington, but has to come from the American people themselves.