Paris: French Prime Minister Manuel Valls has cautioned French citizens that they have moved to a different age, saying that "terrorism is now part of our everyday lives for a long period of time". At least 84 people were killed, and around 300 more injured on Thursday night when a truck crashed into a crowd in the city of Nice during France's national day celebrations, Xinhua news agency reported. In an interview with the French newspaper Journal Du Dimanche (JDD) published on Sunday, Valls said, "Some irresponsible politicians say that this attack could be avoided. But there is no such thing with zero risk." "I have always told the truth about terrorism: We are facing a war, there will be further attacks. It is hard to say, but more lives will be lost. It will take a long time," stressed Valls. Following the Nice attack, three days of national mourning were declared. Meanwhile, the investigation into the attack is going on.