Update 6: As noted earlier, the package in the train station contained either a decoy or a bomb. And now the police, which blew it up, is unsure which. According to a police spokesman, "either it was a very professional decoy or an actual bomb."

For the sake of preserving public calm, let's just assume it was the former.

Update 5: It appears the all clear may have been given early: the latest from HAZ, google translated:

The police confirmed the explosion. Apparently had noticed on the train before a suspect passengers. When she responded this, they fled. The alerted police investigated the abandoned package with explosives dogs, they beat on. In a subsequent X-ray examination was found that were in the packet cable, circuit boards, and a cell phone. Thereupon the experts to blow up controls the alleged bomb determined.

And then:

Now the police seeks to determine whether there was indeed a bomb or just a dummy. In addition, the police are still after the fugitive offender. Given the picture of surveillance cameras should be evaluated at the main station.

So was it a bomb or just a "circuit board, cables and a cell phone"? And who is this "fugitive offender"

Update 4: HAZ reports that the Lanes 9 and 10 at the local train station has been reopened. HAZ adds that the disposal of the "unknown object" was successful and the object was rendered harmless.

Update 3: the current center of action is the train station where moments ago Germany's HAZ.de reported that a bomb disposal unit hs entered the train station.

Latest from Hannover: bomb disposal team enters train station https://t.co/9hS2ewh2Fw pic.twitter.com/L6SPZAbiuk — zerohedge (@zerohedge) November 17, 2015

Update 2: During a press conference, a German official says no explosives found and no arrests made in Hanover. The German official, Pistoris, when asked if a bomb was found in an ambulance, would not confirm.

Update: AP is now reporting that second stadium in Hanover has been evacuated.

From The Telegraph:

Two stadiums in Hannover have been evacuated amid bomb scares at a football match which Angela Merkel was due to attend. The Germany v Netherlands football match has been cancelled and the stadium evacuated. Reports suggest that a truck bomb was hidden in an ambulance, parked outside. But 90 minutes before play was scheduled to start, and 15 minutes after the gates had opened, police announced to fans by megaphone that the game had been cancelled. Volker Kluwe, the police chief in the city, told German public broadcaster NDR that the alleged threat involved the "detonation of explosives in the stadium." Local trains were ordered not to stop at the stadium and other stops around the city. The second venue is a concert hall in Hannover. Concert-goers had been waiting for the band Soehne Mannheims to play when they were told to evacuate the building. It is not yet clear why they are have been told to leave.

Latest (via kreiszeitung.de)

Four days after the terrorist attacks in Paris was canceled shortly before the scheduled kick-off in Hannover the international football match between Germany and the Netherlands. According to information from the local paper, an ambulance has been discovered with explosives. In the field of the stadium in Hanover is a so-called troublemaker have been seen, which is known to the authorities. Security forces have also discovered an ambulance, which housed explosives

The officers at the roadblocks near the stadium now control also police cars and ambulance stations who want in the area. There are rumors that an emergency vehicle was loaded with explosives.

.

This is the local report that alleges ambulance with explosives inside found at stadium. No confirmation. https://t.co/3gcDWL5hKN — Chris Urquhart (@chrisurquhart) November 17, 2015

BREAKING: Hanover chief of police: "There was a device intended to be detonated inside the stadium." #GERNED — DW Sports (@dw_sports) November 17, 2015

BREAKING: Reports that German police have discovered a truck bomb disguised as an ambulance near football stadium in Hanover. #GERNED — DW Sports (@dw_sports) November 17, 2015

Police in Hanover: "You don't know what a perpetrator is possibly planning. Don't stay in groups. Find safety." #GERNED — DW Sports (@dw_sports) November 17, 2015

Recent Update:

*HANOVER POLICE HAD WARNING OF PLAN FOR STADIUM EXPLOSION

*HANOVER POLICE SUPERINTENDANT COMMENTS IN TV INTERVIEW

GERMAN GSG9 ANTI-TERROR COMMANDO ENROUTE TO HANNVOER, BILD SAYS

*GERMANY-NETHERLANDS GAME CANCELED DUE TO `CONCRETE THREAT': WSJ

The soccer stadium in Hannover, Germany, is being evacuated and stadium loudspeakers say the game has been cancelled. The stadium was hosting a match between Germany and the Netherlands. Many top German officials, including Chancellor Angela Merkel, were scheduled to attend the match to show they will not bow to terrorism.

On Friday, a match between Germany and France in Paris was the site of numerous explosions in a terror attack that killed at least 129 people throughout the city. One of the attackers reportedly attempted to enter the stadium with a ticket after the game had begun but was turned away. He then detonated his explosive vest. In addition to the game in Germany, France and England are scheduled to play a friendly at Wembley Stadium on Tuesday afternoon. However, Tuesday's scheduled match between host Belgium and Spain was cancelled on Monday amid security concerns, and many fans were worried that it might mean the disruption of Euro 2016 next year. Tournament organizers said earlier in the day (before the Hanover evacuation) that the event would go on, however. We will update this post as news comes in. As we detailed earlier,

Anxiety remains high across Europe. The Germany-Netherlands soccer exhibition match scheduled to be held in Hanover tonight has been canceled, city police spokeswoman Stephanie Weiss says by phone. While no reason was confirmed, DPA reported the discovery of a suspicious suitcase earlier (which police said posed no threat).

Massive confusion here at hannover as match cancelled after letting first batch of fans in... @BBCBreaking pic.twitter.com/aOyzW4MWbu — Dion Farnes (@DionFarnes) November 17, 2015

As DPA reported earlier,

Police sealed off the stadium for the friendly international between Germany and the Netherlands for half an hour Tuesday after the discovery of a suspicious suitcase. The stadium and some roads in the area were closed before police said little over two hours before kick-off that the object posed no threat. Extra police, many armed with automatic weapons, has been deployed for the game as security was beefed up after the terror attacks in Paris on Friday. All available police officers were being deployed in Hanover, a police spokeswoman said without giving further details. The German football federation (DFB) had considered calling off Tuesday's match as Germany were playing France at the Stade de France north of Paris when the attacks occurred. However federation and team officials agreed to go ahead with the friendly international in solidarity with France and the relatives and victims of the Paris attacks. Chancellor Angela Merkel and several senior cabinet members are due to attend the match at the HDI Arena. Several thousand tickets for the game remained unsold at midday and unlike previous internationals or Bundesliga games in Hanover few fans were seen in the city centre hours before the game.

But now:

*HANOVER POLICE SPOKESWOMAN CONFIRMS GERMAN-DUTCH GAME SCRAPPED

*HANNOVER STADIUM HOSTING GERMANY-NETHERLANDS EVACUATED, AP SAYS

Verkeer chaos richting stadion Hannover, verdacht pakketje gevonden, bron @ad pic.twitter.com/V94bJtQSZs — Kale Real Dutchmen (@Itsmekale) November 17, 2015