A German soccer stadium and concert arena were evacuated less than two hours before a friendly match between Germany and the Netherlands Tuesday after police uncovered a "concrete" bomb threat.

It happened just four days after the Paris attacks that targeted a stadium and several restaurants, killing more than 120 people Friday.

"We had concrete evidence that someone wanted to set off an explosive device in the stadium," Hannover police chief Volker Kluwe told German TV. Referring to another bomb threat about an hour beforehand that turned out to be a false alarm, Kluwe said, "After the first object turned out to be harmless, we got a tip that had to be taken seriously that an attack was being planned."

Investigators found a suspicious suitcase inside or near the stadium and a second suspicious device at the city's central train station, German media and Sky News reported. Police closed off part of the train station.

German police later said no explosives were found, but the game was called off over "indications it would not be safe."

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Germany's top security official said that providing details about the threats that led him to cancel the soccer match could unsettle Germans and make future such decisions harder.

Interior Minister Thomas de Maiziere declined to answer questions about the exact nature of the threat and the source of the information during a news conference Tuesday night after the Germany-Netherlands match was canceled.

De Maiziere asked for "trust," saying "some of these answers would unsettle the population, some of these answers would make our actions in future harder and (...) some of these answers might lead the source of the information not to provide tips to us anymore."

The German daily Bild newspaper reported authorities had received a warning that an attack using explosives and automatic weapons was planned

The nearby TUI-Arena was evacuated as well, and a planned concert from the German pop band Soehne Mannheims was canceled.

At the same time as the German threat, players and fans of the French and English soccer teams united in a symbol of defiance and respect at Wembley Stadium at a friendly game staged four days after the deadly attacks in Paris.

In a touching pre-game ceremony, supporters from England and France sang the French national anthem, before the squads came together around the center circle to observe a minute's silence in honor of the 129 people killed.

Wembley Stadium's iconic arch was lit up in the blue, white, and red of the French flag, while the French motto "Liberte, Egalite, Fraternite" was projected on the front of the national stadium.

England won 2-0, but the atmosphere was subdued throughout the game.

"Tonight is more about solidarity than football," England fan Robert Williams, who was wearing a beret and holding a French flag, told the Associated Press before kickoff. "It is about remembering the people that have lost their lives in such tragic circumstances."

Prince William, who helped lay floral tributes beside the field, and British Prime Minister David Cameron were among the 71,223 spectators at Wembley, where there was an increased police presence and enhanced security measures that included compulsory bag searches.

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The Associated Press contributed to this report.