Brussels Rocked by Airport, Metro ExplosionsAt least three explosions rocked Brussels Tuesday morning - two at the airport and one at a metro station in the heart of the capital, with local media reporting more than 20 dead and many others injured in the airport blasts. Footage showed people fleeing the Zaventem airport, as a double explosion at about 8 am local time shattered the massive windows, leaving glass and tile scattered on the airport floor and smoke curling into the chilly morning air. Local media reported a third unexploded bomb had also been discovered. Suicide attack confirmed\n\nMedia reports say a Belgian prosecutor has confirmed a suicide attack at the Brussels airport. Local media also reported shouts in Arabic at the airport before the explosions. At least one other explosion was reported at the Maalbeek metro station in downtown Brussels, where many European Union institutions are based, at the height or rush hour - at around 9 am local time. Local media described people emerging from the metro with burns and wounds and panic on the street. High alert \n\nBelgian authorities put the country on the highest level 4 alert. “We are following the situation minute by minute,” Belgian Prime Minister Charles Michel tweeted. “The first priority goes to victims and those inside the airport.” Brussels airport has cancelled all flights, and metro, museums and train stations have been closed. Authorities have called on commuters to stay home from work and those already at their offices to remain there. Revenge possible motive \n\nWhile the cause of the explosions remains unclear, they come just days after the arrest of key Paris attacks suspect Salah Abdeslam in Brussels that have raised fears of revenge attacks to follow. They also bring to mind the November 13 bombings and shootings that took place in several places around the French capital. A passenger called Veronique who had been waiting to register for a flight to France, described the chaos inside the Brussels airport. “There were lots of military around with their dogs. I heard the sound of a door closing and a dog running and then it exploded and then we all started running,” she told French radio, with sounds police sirens ringing behind. Starbucks, US flights targeted \n\nPassengers described the blasts taking place at a Starbucks cafe and in the terminal for flights to the United States. “We were 3 hiding, we didn’t know whether to come or go,” another airport passenger who hid with others during the blasts told France’s BFMTV.