Relief agencies are rushing aid to southern Kygyzstan where four days of ethnic conflict have claimed 124 lives and caused a "humanitarian catastrophe."

The fighting, which involves ethnic Kyrgyz and Uzbeks, has devastated the southern capital of Osh and neighboring Jalalbad and is considered the worst violence in the country since April's revolution that ousted President Kurmanbek Bakiyev, who is now in Belarus where he has been given asylum.

Some have blamed the violence on "provacateurs" hired by supporters of Bakiyev although no official cause for the conflict has been named.

Both Kyrgyz Interim President Roza Otunbayeva and Bakiyev have appealed to Russian authorities to send troops to help bring peace to the region.

Meanwhile, an estimated 50,000 to 100,000 Uzbeks have fled to neighboring Uzbekistan for fear of their lives.

The International Committee of the Red Cross (ICRC) called the situation a "humanitarian catastrophe" and has appealed for $8.8 million to aid victims.

An ICRC cargo plane of emergency supplies and body bags was airlifted to Osh on Sunday.

Twelve additional flights carrying a cargo of suture equipment, wound dressings and other surgical materials as well as household items, such as jerrycans, buckets and tarpaulins for 20,000 families, are scheduled to arrive in Osh in the coming days.

United Nations officials, meanwhile, expressed gratitude to the Uzbekistan government for welcoming the refugees, and pledged to "support their efforts and assist tens of thousands, mostly women and children, seeking safety."

The U.N. has also voiced deep concern over the reported brutality of the violence, which they say involves "indiscriminate killings, including of children, and rapes."

"This is a very dangerous situation, given the ethnic patchwork in this part of Kyrgyzstan, as well as in neighbouring areas of Uzbekistan," said U.N. High Commissioner for Human Rights Navi Pillay, adding a plea that a reported shoot-to-kill policy adopted by Kyrgyzstan authorities be halted.

"The right to life and the right not to be tortured cannot be set aside during an emergency," Pillay said. "Security forces need to be given strict instructions to avoid unnecessary force, and to steer clear of taking sides in the conflict, while still doing their utmost to bring an end to the violence."