The U.N. refugee agency (searchbegan pulling foreign staff out of large swaths of southern and eastern Afghanistan (search) on Tuesday in the wake of the killing of a French worker, a decision that could affect tens of thousands of Afghan returnees.

Some 30 foreign staff members were being withdrawn, and refugee centers in the Afghan provinces of Nangarhar, Paktia, Khost and Kandahar were being closed, said Filippo Grandi (search), the chief of mission in Afghanistan with the United Nations High Commissioner for Refugees.

"We are taking today a painful decision to temporarily reduce staff in the eastern and southern province," said Grandi. "We will review the situation after two weeks."

The decision follows a series of attacks on the United Nations in recent days, including the killing of Bettina Goislard, a 29-year-old refugee agency worker, as she traveled through a bazaar in the city of Ghazni, 60 miles southwest of the capital.

That same day saw a bomb attack on a U.N. vehicle in eastern Paktia province. And on Nov. 11, a car bomb exploded outside U.N. offices in Kandahar, injuring two people.

Several international aid organizations operating in the south also held an emergency meeting to discuss "options which may include the withdrawal from the southern region of Afghanistan," according to ACBAR, an umbrella group of 86 aid agencies working in Afghanistan.

The group quoted Anne Wood, a senior coordinator for Portland, Oregon-based Mercy Corps, as saying: "The situation continues to deteriorate. We do not believe that measures taken so far ... will effectively address the deepening crisis. In the south, we are now at a critical juncture."

Grandi appealed to the international community to do more to improve security in Afghanistan. A NATO-led peacekeeping force operates in the capital, Kabul, but has not yet been expanded throughout the country, where warlords hold sway and Taliban and Al Qaeda militants launch frequent attacks.

"If reconstruction of the country is to continue, governments must consider more seriously helping Afghanistan achieve security and stability," Grandi said. "We cannot do this alone. This murder tragically proved it."

Some 3 million Afghan refugees and internally displaced people have returned to the country since the fall of the Taliban regime in late 2001, mostly from Pakistan and Iran. UNHCR said its Afghan staff would remain to help keep aid and support flowing to more than 220,000 Afghan returnees affected by the decision.

Also Tuesday, the refugee agency announced that Goislard's body would be buried in Afghanistan in accordance with her wishes. Goislard had worked in Afghanistan for more than a year, learning the local language and becoming close to many refugees and officials.