Several feared dead as Brussels airport, metro rocked by explosions

- Note: This article is being updated as more information comes in.

Two explosions targeted the main hall of Zaventem Airport at around 8:00am (0700 GMT), with a third hitting the Maalbeek metro station just as commuters were making their way to work in rush hour.

Belgian media reports said at least 13 people had been killed and 35 injured at the airport, while an AFP reporter said at least 15 people with bloodied faces were being treated by emergency services outside the metro station.

More than a dozen people were lying on the pavement outside the station, being treated by emergency service for facial wounds.

There were chaotic scenes at the airport as passengers fled in panic, with a thick plume of smoke rising from the main terminal building.

The blasts smashed the windows of the departure hall and sent ceiling tiles shattering to the floor.

Witnesses told Belga news agency there had been shots and shouts in Arabic at the airport before the blasts hit.

Federal police told Belga they could confirm one person had been killed in the blasts at the airport on the northwest outskirts of Brussels.

"There have been two explosions at the airport. Building is being evacuated. Don't come to the airport area," the airport said on Twitter, as police cars and rescue vehicles rushed to the scene.

Interior Minister Jan Jambon announced that Belgium's terror threat had been raised from three to a maximum of four, while in neighbouring France, a source at Paris' Charles de Gaulle airport said the facility was boosting its security in response.

Security was also reinforced at Frankfurt airport, German police said.

The blasts triggered a transport shutdown, with all flights halted in and out of the airport on Brussels' northwest outskirts and the city's metro system suspended.

"All airport operations have been suspended until further notice," the airport said Twitter.

Public broadcaster RTBF said regional authorities had gone into emergency mode.

Shocked and Concerned

"We heard the explosion and felt the blowback," Jean-Pierre Lebeau, a French passenger who had just arrived from Geneva, told AFP, adding that he had seen wounded people and "blood in the elevator".

"First we were kept together by the border police, then they gave us the order to evacuate," Lebeau said.

The ceilings collapsed, he said, describing a smell of gunpowder at the scene.

With shock on their faces, Jean-Pierre Herman embraced his wife Tankrat Paui Tran, who he had just gone to collect from the airport after her flight from Thailand.

"My wife just arrived," Herman said. "I said hello, we took the elevator and in the elevator we heard the first bomb.

"The second exploded just when we got off. We ran away to an emergency exit. I think we are very lucky."

An AFP correspondent on their way to the airport said roads to the terminal had been blocked and trains halted.

There was no immediate confirmation of the cause of the blasts.

Video showed devastation inside the departure hall with items scattered across the floor.

The blasts come days after the dramatic arrest in Brussels on Friday of Saleh Abdeslam, prime suspect in the Paris terror attacks that killed 130 people in November, after four months on the run.

French investigator Francois Molins told a news conference in Paris on Saturday that Abdeslam, a French citizen born and raised in Brussels, admitted to investigators he had wanted to blow himself up along with others at the Stade de France on the night of the attack claimed by Islamic State; but he later backed out.

Metro Explosions

An explosion occurred at a metro station in Brussels close to the European Union's institutions in the Belgian capital, subway staff said.

The blast occurred shortly after 0800 GMT, in the morning rush hour, at Maalbeek station. TV images showed black smoke billowing from the station entrance.

More than a dozen people were lying on the pavement outside with bloodied faces and were being treated by emergency services.

The metro operator later has since said all metro stations are closing down.

The European Commission, the executive arm of the European Union, told staff to remain indoors or stay at home.

Security Increased

Dutch counter-terrorism officials said  they were boosting security at national airports and tightening controls on the southern border with Belgium.

"Out of precaution we are taking a number of additional measures in the Netherlands," the Dutch coordinator for terrorism and security said, adding there would be "extra police patrols at Schipol, Rotterdam and Eindhoven and border controls on the southern border".

Security measures have also been reinforced at the Charles De Gaulle airport in Paris following Tuesday's bombings in Brussels, an airport source said.

A full deployment of security officials was underway at all eight terminals of the international airport and its two railway stations, with reinforced checks on trains arriving from Brussels, said the source.

London's Gatwick airport stepped up security as British Prime Minister David Cameron prepared to hold an emergency cabinet meeting on the attacks.

"As a result of the terrible incidents in Brussels, we have increased our security presence and patrols around the airport," the airport said in a statement.

Greek carrier Aegean Airlines said on Tuesday it suspended all its flights to and from Brussels, with its morning flight to the Belgian capital diverted to Dusseldorf.

Stocks Fall

Shares in airline and travel sector companies dropped sharply across European stock markets after the explosions.

The STOXX Europe 600 Travel and Leisure index fell 2.2 percent, the top decliner, with shares in easyJet, Ryanair, Accor, InterContinental Hotels and IHG down by 2.4-4.6 percent.

The pan-European FTSEurofirst 300 index was down 0.7 percent, while Belgium's benchmark share index was down 0.5 percent.

Meanwhile the yen and the Swiss franc climbed on Tuesday as the news spurred inflows into traditional safe-haven currencies and assets.