July 3 (Bloomberg) -- Pakistan’s 2 million refugees displaced by fighting in the northwestern Swat Valley are facing the threat of disease as they cope with damaged water and sewage systems in towns and villages, the United Nations said.

“There are major challenges facing the displaced and those still caught in the conflict areas,” Eric Laroche, assistant director-general of the Health Action in Crises Cluster of the World Health Organization said yesterday. “Health facilities have been damaged or destroyed” in these areas.

Most of the displaced people are living with host communities, which has put the region’s heath-care system under “enormous strain,” the UN said.

Pakistan’s government said June 30 that civilians may be able to start returning to towns and villages within a week. The fighting produced the largest exodus in Pakistan since the country’s founding in 1947 and the UN said last month only about a quarter of the funds it requested for the refugee crisis have been received.

Displaced people are threatened with diarrhea, measles and respiratory infections as a result of the strain on the health service, Laroche said. So far, the WHO’s early warning system has managed to identify and control more than 30 potential communicable disease outbreaks, he said.

Civilians began leaving their homes last month in the South Waziristan region after the military said it will expand its operations against Taliban militants into the Federally Administered Tribal Areas bordering Afghanistan. It may also start operations in North Waziristan after militants scrapped a 16-month-old peace accord last weekend.

Crisis to Worsen

The new offensives will worsen the refugee crisis, Amnesty International said in an e-mailed statement today.

“A displacement crisis the government said would last only for weeks looks set to go on for months with no relief in sight,” Sam Zarifi, Amnesty’s Asia-Pacific director, said in the statement. “To make matters worse, the vast majority of displaced people are living outside the registered camps where aid agencies” are distributing aid.

Pakistan’s central and regional governments need to do more to ensure aid reaches these people, Amnesty said.

Security forces killed 23 militants and captured five in the Swat Valley and Dir districts, the military said yesterday. Militants in South Waziristan fired rockets at Jandola Fort without causing any casualties, it said.

In the city of Rawalpindi, a suicide bomber rammed his motorcycle into a bus carrying government employees yesterday, killing one person and injuring 29, according to police. Rawalpindi is home to the headquarters of Pakistan’s army and is adjacent to the capital, Islamabad.

The military says it has killed more than 1,600 militants in the past eight weeks in the Swat operation. The Taliban have said they will attack Pakistani cities with suicide bombers in retaliation for the army’s offensives.

To contact the reporters on this story: Paul Tighe in Sydney at ptighe@bloomberg.net; Khalid Qayum in Islamabad at kqayum@bloomberg.net.

Last Updated: July 2, 2009 23:26 EDT