Story highlights The cell planned to attack Dusseldorf's old town, German attorney general says

Arrests followed a tip from another suspect held in French custody since February

(CNN) Three Syrian men were arrested Thursday in Germany on suspicion of planning a terror attack on Dusseldorf on behalf of ISIS, the German attorney general's office said.

The cell -- which allegedly included an experienced bomb maker -- was plotting a mass casualty attack on the old town of the western German city, using suicide vests and guns, federal prosecutors say.

There were no indications that the plot, believed ordered by senior ISIS leadership, was in an advanced stage of implementation, the statement said.

All Syrians

The three were apprehended separately Thursday in the states of North Rhine-Westphalia, Brandenburg and Baden-Wurttemberg, the attorney general said in a statement.