France had been on high alert for terrorism since the '' Charlie Hebdo '' shooting and a series of related attacks in January by militants belonging to Al-Qaeda in the Arabian Peninsula , and had increased security in anticipation of the 2015 United Nations Climate Change Conference , scheduled to be held in Paris at the beginning of December , as well as reinstating border checks a week before the attacks
a series of related attacks
January 2015 Île-de-France attacks
November 2015 Paris attacks