President Barack Obama made an unannounced visit to the French Embassy in Washington on Thursday to pay his respects and express solidarity with the French people after a deadly attack on a satirical newspaper in Paris.Shortly after returning from a trip to Phoenix, Obama rode in his motorcade to the embassy to sign a condolences book. He was joined there by the French ambassador, Gerard Araud.Obama wrote in the book that he extended US sympathy and solidarity to the French people following Wednesday's attack at the Charlie Hebdo weekly in which 12 people were killed."As allies across the centuries, we stand united with our French brothers to ensure that justice is done and our way of life is defended. We go forward together knowing that terror is no match for freedom and ideals we stand for - ideals that light the world," he wrote.On Air Force One earlier, Obama got an update via conference call from his national security advisers on the Paris shootings. He also heard about security issues facing Americans in the United States and around the world, the White House said.White House spokesman Josh Earnest told reporters that US officials have said there is no indication of a specific threat to Americans related to the Paris shootings.