KANDAHAR, Afghanistan - Security concerns are making it difficult for aid agencies to help thousands of families who have been displaced by fighting and drought in southern Afghanistan.

A United Nations spokeswoman in Geneva estimates that almost 5,000 families have been displaced in Helmand province, where NATO and Afghan troops have been battling the Taliban for months.

The difficulties for relief agency can be seen in neighbouring Kandahar province, where five members of an Afghan medical team have been kidnapped by insurgents near a refugee camp.

A senior Afghan official says the Taliban have threatened to kill members of the team unless the government releases insurgent prisoners.

The UN estimates that 15,000 families were displaced last summer during intense fighting between Canadian forces and the Taliban in the Panjwaii and Zhari districts.

The UN says most of those people have returned to their homes, but some have not because of fear and security concerns.