Google News - Geneva - More than 2 000 Somalis have fled across the border to Kenya over the last two days amid reports of advances by Islamist forces on several Juba Valley towns, the United Nations refugee agency said on Friday.

Jennifer Pagonis, spokesperson for the United Nations High Commissioner for Refugees (UNHCR), said the influx coincided with reports that fighters allied to the Islamic Courts Union took the southern Somali towns of Afmadow and Buale this week.

About 30 000 people from Somalia have sought refuge in Kenya since the beginning of this year. Pagonis said continued arrivals could soon overwhelm existing refugee camps or strain water resources in the Kenyan town of Amuma.

The Islamic Courts Union seized the capital Mogadishu from US-backed warlords in June and has taken control of parts of southern Somalia, challenging efforts by President Abdullahi Yusuf to impose central rule on the country of 10 million people for the first time since 1991.

On the Horn of Africa's northern coast, Somali authorities have been detaining or sending to Mogadishu many would-be migrants - irrespective of their nationality or status - looking to cross the Gulf of Aden toward Yemen, Pagonis said.

Pagonis said the Somali efforts may be misdirected.

"Any crackdown should target the smugglers, not the refugees, asylum seekers and desperate migrants they prey upon," she told a UN news briefing in Geneva.

More than 3 500 people, mainly Somalis and Ethiopians, have sailed to the Yemeni coast since early September, most intending to reach richer Arab states. At least 54 people have died and 60 have gone missing in the period in the hands of smugglers who charge about $70 (about R540) for the voyage, Pagonis said.

As a result of the crackdown in the northern port town of Bossasso, reported to UNHCR staff by migrants arriving in Yemen, she said boats appear to be using new departure points along Somalia's long Gulf of Aden coastline.