The Belgian Red Cross has put out an appeal for A and O negative blood donations in Brussels following a major attack on an airport and a metro station which has killed at least 30 people.
In a statement on its website, the charity has sent out an appeal specifically targeted at those two blood types.
A spokesman for the charity told Belgian broadcaster RTBF: "First, we are only asking for O negative, A negative donors".
He confirmed three ambulances filled with blood bags were en route to Saint-Pierre hospital where the victims are being treated.
At least 55 people are believed to have been injured - at least 10 critically - in three explosions which struck the city around 7am (8am GMT).
Belgian journalist Sandrine Beigas tweeted there was a large security presence outside the hospital.
Video shows people fleeing from the airport terminal after an explosion near the American Airlines check-in desk at Zaventern aiport.
Men were reportedly heard "shouting in Arabic" and some witnesses say there were the sounds of gunfire before two explosions hit the terminal.
Minutes later, another attack hit the Mallbeek metro station in the city.
Additional reporting by agencies
