BRUSSELS, March. 22 -- The terror threat level in Belgium has been raised to the maximum, level 4, after two explosions in the departures hall at Brussels airport on Tuesday morning.

The Belgian federal police has confirmed one dead and multiple injuries. Several Belgian media are reporting at least 11 fatalities and 25 injured.

One airport worker told Flemish public broadcaster VRT. "I was on my break and heard and felt a huge explosion. We can see the departures hall from here, and I saw a plume of smoke rising up. The windows are completely shattered. People are walking around in shock."

A video on Twitter showed crowds running from the terminal in panic amid broken glass and heavy smoke.

Trains and other public transport to the airport have been cancelled, the Belgian national rail operator SNCB said. Emergency services are in attendance, and no flights are currently landing or taking off.

BEIJING, March 22, 2016 -- File photo taken on April 20, 2010 shows a passenger plane on a runway at Brussels Internatinal Airport in Brussels, Belgium. Explosions were heard at Zaventem Airport in Brussels shortly before 8 a.m. March 22, 2016 local time, where several people were injured, Belgium's RTBF quoted witnesses as reporting. (Xinhua/Wu Wei)