Victims lay in pools of blood, their limbs blown off, as the smoke cleared to reveal scenes of horror after twin explosions ripped through the main terminal at Brussels airport, witnesses told AFP.
The normally-bustling check-in hall at Zaventem airport was wrecked by the morning rush-hour blasts, with part of the ceiling collapsing near the airline desks and many of the huge plate-glass windows blown out.
"A man shouted a few words in Arabic and then I heard a huge blast," airport baggage security officer Alphonse Lyoura told AFP, with blood still on his hands.
There was another explosion about two minutes later.
"It was total panic everywhere... I saw people lying on the ground covered in blood who were not moving," Lyoura said.
"At least six or seven people's legs were totally crushed. A lot of people lost limbs. One man had lost both legs and there was a policeman with a totally mangled leg."
Emergency services said 14 people were killed at the airport, with more than 90 injured.
Shortly afterwards, another explosion ripped through a train at Maalbeek metro station, killed around 20 others, and wounded more than 100 people.
The city was already on high alert following Friday's arrest of Salah Abdeslam, a key suspect in the November attacks on Paris that killed 130 and were claimed by the Islamic State group.
Brussels-based Briton Julian Firkins, 44, was in the departure terminal with his partner close to where the first bomb went off.
"We had been waiting in line when I decided to get a tea. Literally five seconds after I left, the first bomb went off right next to us," Firkins said.
He ran back to his girlfriend just as the second blast rocked the hall, wreaking further carnage which they miraculously escaped.
Michel Mpoy, 65, who was at the airport to pick up a friend arriving from Kinshasa, said it was "a total mess -- it was terrible".
Another person waiting at the airport was Jean-Pierre Herman who had just met his wife off a flight from Thailand.
"I said 'hello,' we took the elevator and in the elevator we heard the first bomb," he said.
"The second exploded just when we got off. We ran away to an emergency exit. I think we are very lucky."
Charlotte McDonald-Gibson, a British journalist living in Brussels, told AFP there had been "total confusion" at the airport, where she was having breakfast before a flight.
"Suddenly staff rushed in and said we have to leave," she said. "Nobody knew what was going on.
"It was total confusion, people were just standing around wondering what was happening."
In the city, AFP journalist Lachlan Carmichael was on the metro when his train was halted in the tunnel after he and the other passengers felt a shock wave from the explosion a hundred or so metres down the line at Maalbeek.
Train staff said there had been an explosion ahead and evacuated the train as it began filling up with smoke, with passengers getting out onto the tracks whose power lines had been switched off.
Another AFP journalist, Cedric Simon, said saw clouds of smoke and dust coming out of Maalbeek station and about 15 people lying by the road, many with bloodied faces who were being treated by medical staff.
The Thon Hotel opposite the station was turned into a makeshift hospital with medics treating about 40 wounded people, general manager Hans Van der Biesen told AFP.
"I saw one person with his leg completely ripped apart. Then there was another person whose head was completely bloody," said Maya Halaoui, a Belgian woman of Lebanese origin who had been in a business meeting at the hotel.
The streets were filled with police cars and emergency vehicles, sirens wailing and blue lights flashing.
Brussels has been on high alert since January 2015 when jihadists stormed the Paris offices of the Charlie Hebdo satirical weekly and a Jewish supermarket, killing 17, with heavily-armed police and then troops deployed on the streets.
Security was further hiked after the November attacks on the French capital, which were hatched by jihadists in Brussels.