Germany's Chancellor Angela Merkel attends a working session at the NATO Summit in Warsaw, Poland July 9, 2016. REUTERS/Kacper Pempel

BERLIN (Reuters) - Militant groups smuggled some of their members into Europe in the wave of migrants who have fled from Syria, German Chancellor Angela said on Monday.

“In part, the refugee flow was even used to smuggle terrorists,” Merkel told a rally of her Christian Democrats in eastern Germany.

More than 1 million migrants arrived in Germany last year, many of them Syrians.