Explosions rocked the Brussels airport and the subway system Tuesday, killing at least one person and injuring many others just days after the main suspect in the November Paris attacks was arrested in the city, police said.

At least one person was killed in two explosions in the departure hall at the Brussels airport, police said. All flights were canceled, arriving planes were being diverted and Belgium's terror alert level was raised to maximum. Security was also tightened at all Paris airports.

"One person has died and perhaps there are several more," said a police official who spoke on condition of anonymity because the situation was developing.

Zach Mouzoun, who arrived on a flight from Geneva about 10 minutes before the first blast, told BFM television that the second, louder explosion brought down ceilings and ruptured pipes, mixing water with blood from victims.

"It was atrocious. The ceilings collapsed," he said. "There was blood everywhere, injured people, bags everywhere."

"We were walking in the debris. It was a war scene," he said.