As the world reels in the wake of a massacre in Paris, world leaders have vowed to fight ISIS. It isn't clear, however, what exactly that fight will entail.

Thousands of soccer fans at Wembley Stadium showed solidarity with France Tuesday, joining in singing of 'La Marseillaise', the French national anthem.

A Chilean mother and her daughter, cut down in a concert hall while the daughter's 5-year-old son survived. A young Italian woman, separated from her boyfriend and friends when the concert erupted in chaos.

The hacker collective Anonymous declared war against the Islamic State group Saturday after a series of brutal attacks in Paris on Friday killed 129 people and injured hundreds more.

It was France's deadliest peacetime attack, deeply shaking the nation.

Thirteen men and a woman go on trial Wednesday over the 2015 attacks against a satirical newspaper and a kosher supermarket in Paris that marked the beginning of a wave of violence by the Islamic State group in Europe.

The only surviving member of the Islamic State cell that attacked Paris in November 2015 refused to rise for a Belgian court on Monday, or answer questions about his actions.

Security measures have continued to increase at the popular French film festival following terrorist attacks in France in recent years.

Early projections indicate that Centrist Emmanuel Macron and far-right leader Marine Le Pen are set to face each other in a May 7 runoff.

A year after Islamic State suicide bombers killed 32 people in Brussels, Belgian authorities say much remains unclear about who ordered the attacks.