Updated

The State Department on Tuesday alerted U.S. citizens traveling to Europe to heightened risks of terrorism, citing events in France and Poland this summer that are expected to draw large crowds.

The European soccer championships and the Tour de France bicycle race, both hosted in France in June and July, could be terrorist targets, the alert said. The Catholic Church’s World Youth Day in Krakow, Poland, in late July, expected to draw up to 2.5 million visitors, will result in stricter security screenings there, the alert said.

The alert was issued because of the start of summer and the approach of high-drawing events, said State Department spokesman John Kirby.

“I’m not aware of any specific, credible terrorist threat around these events or in any particular place in Europe,” Kirby said, adding the alerts were based on an “accumulation of information.”

“We took the opportunity because it’s the beginning of summer, to make our concerns known,” he said.

The message distributed Tuesday was an alert, not a warning. Warnings are seen as indicative of a higher-level threat. The State Department often issues alerts for large-scale events, such as the Olympics.

The State Department last issued a travel alert for Europe in March after terrorist attacks in Brussels killed nearly three dozen people. That message said terrorist groups continue to plan attacks throughout Europe in such public venues as sporting events and tourist sites.