Two pictures of the gunman suspected of carrying out the shootings at the offices of French newspaper Liberation and a bank have been released.
Police believe the lone gunman is responsible for the attack at the newspaper in Paris as well as three other incidents.
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Mr Kim has made two recent visits to China.
The study looked at the development of 422 children over the course of eight years.
The president said they will come into force if China refuses to change its practices.