A strong quake measuring 7.3 on the Richter scale struck Haiti on Tuesday, causing huge casualties and damages and leveling many houses in capital Port-au-Prince to the ground.

Among the victims, 16 U.N. staff members have been confirmed dead in the quake so far, and the number is expected to rise as scores of U.N. staffers are still listed missing.

U.N. peacekeepers or humanitarian staff from many countries and regions came to Haiti to help maintain security and stability of the country. Some had completed their mission and were about to return to their home countries. All of a sudden, a natural disaster claimed their lives.

They had gone through untold hardship and overcame homesickness to perform their duty since they chose to work under the blue U.N. flag in regions torn by war or hit by disasters far away from their homeland.

When the quake struck Haiti, they were among the first to rise to their feet and start rescue and relief operations amid waves of aftershocks. As some media reports put it, hours after the quake, vehicles and peacekeepers with U.N. logo were seen rescuing victims. What a moving scene in the disaster areas when people were yet to recover from the panic!

We may describe the devotion and sacrifices of these U.N. personnel in time of disaster as "internationalism" -- a word that embodies the spirit of humanitarianism, the faith in world peace and harmony among the mankind.

This explains why helping hands come from far and near soon after the quake hit Haiti. Disasters befall our planet more frequently in recent years, yet what is more noteworthy is the solidarity among people across the globe when misfortune strikes.

Hand in hand, the world stands as one in the face of common challenges, regardless of race, religious belief or ideology.