Funerals were held today in Paris and Jerusalem for three French police officers and four Jewish victims killed in terrorist attacks in Paris.
The mourning comes as authorities try to find out more about the men who were allegedly involved in those attacks.
Those men claim they had links to Al Qaeda in the Arabian Peninsula and so-called Islamic State.
In the U.S., the FBI is investigating what it's calling an "intrusion" into the Twitter and YouTube accounts of the U.S. Central Command. Hackers claiming to be affiliated with the Islamic State are taking responsibility for the "intrusion."
Jim Walsh, an expert in international security at the security studies program at MIT, joins Here & Now's Robin Young to discuss the latest in both the French and American investigations.
This segment aired on January 13, 2015.