GENEVA, March 11 (Xinhua) -- Flags flew at half-mast on Monday at the United Nation's European headquarters in Geneva as staff from UN agencies and associated organizations mourned the loss of colleagues aboard the Ethiopian Airlines flight which crashed on Sunday.

An Ethiopian Airlines Boeing 737 MAX 8 bound for Nairobi, Kenya, crashed shortly after taking off from the Ethiopian capital Addis Ababa Sunday morning local time, killing all 157 people on board, including eight crew members.

"Yesterday's terrible air crash in Ethiopia took the lives of all those on board -- including at least 21 of our UN colleagues, according to the latest information, not to mention an undetermined number of people that have been working closely with the UN," the UN said in a statement.

Those killed in the crash of Ethiopian Airlines flight ET302 included UN staff, delegates, and others, many of whom were on their way to the United Nations Environment Assembly in Nairobi, said the UN.

According to Michael Moller, director-general of UN Geneva, those working in the UN building observed a minute of silence at noon on Monday to show solidarity with the victims, including the UN colleagues in the UN system.

The UN Refugee Agency, UNHCR, said it was mourning the loss of three colleagues, two mothers, and a father, killed in the crash, while a staff member of the International Organization for Migration (IOM) was also killed.

"We've been struck by a sudden and terrible loss," said the UN High Commissioner for Refugees, Filippo Grandi, cutting short a visit to the Middle East and urgently returning to UNHCR headquarters in Geneva.

"This is devastating for all families who lost their dear ones in yesterday's crash. Our thoughts are with them."

Among the victims, 32 are from Kenya, 18 from Canada, nine from Ethiopia, eight each from China, Italy and the United States, seven each from Britain and France, six from Egypt, and the remaining from more than 20 other countries, said the airline.