The UN and human rights groups have warned that the imminent arrival of monsoon rains could see tents in state-run camps being flooded with sewage, and lead to outbreaks of disease.

But officials argue that enough drainage ditches have been dug to cope with excess water at the camps, where some 250,000 Tamil civilians are currently held.

The government says it is detaining Tamils in camps so that they can be screened for former Tamil Tiger fighters.

Al Jazeera's Wayne Hay reports.