Investigators are aware of additional ISIS plots in Europe, possibly linked to the Paris and Brussels networks.

A combination of electronic intercepts, human sources and database tracking indicates several possible targets had been picked out by ISIS operatives in the months since the Paris attacks, say U.S. counterterrorism officials.

Since this week’s attacks in Belgium, information found in a raided apartment, including maps, indicated other potential targets had been chosen, one of the sources said.

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