International aid agencies say nearly 50 people have been killed and more than 3,000 left homeless, after torrential rains caused a river to burst its banks in Somalia's Middle Shabelle region.  The rains have also reportedly slowed an Islamist advance into the western Gedo region, where a government-allied militia is said to be preparing for battle.

Aid workers say the town of Jowhar and the surrounding area has been devastated by the flooding of the nearby Shabelle River in southern Somalia.  Jowhar is an Islamist-controlled town, about 90 kilometers northwest of the capital, Mogadishu.

David Gilmore is the country director for Somalia and southern Sudan for the non-governmental aid organization, CARE International.  He says days of heavy rainfall caused the river to flood as many as 170 villages and 1,500 hectares of farmland.

"The torrential rainfall is not just affecting the people close to the river, which is bursting its banks.  It is also affecting road transport, where much-needed relief supplies and food have been cut off to communities, which have been affected by consecutive years of drought," he said.

Heavy rains in the country and in the Ethiopian highlands have also caused localized flooding in southwestern Gedo, the second largest region of Somalia and bordered by Ethiopia and Kenya. 

Residents there say that nearby Juba River topped its banks early Wednesday, killing nearly a dozen people and sending thousands of villagers fleeing to higher ground.

The flooding has reportedly slowed down an alleged push by Islamist fighters to attack and capture one of Gedo region's most populace towns, Baardheere.  The town is the stronghold of the Juba Valley Alliance, a militia loyal to Somalia's secular and internationally-backed interim government in Baidoa.

On Wednesday, Juba Valley Alliance leaders warned that an attack was imminent and vowed to defend the town.  But Islamist leaders in Mogadishu said that they had no intention of fighting, while the area remained affected by the rains.

Somali Islamists took power in early June, after capturing Mogadishu from factional leaders.  Since then, they have gained control of important ports and airfields across southern and central Somalia, while the weak government has been confined to the town of Baidoa. 

Ethiopia, which accuses Islamist leaders of trying to turn Somalia into a terrorist haven, is believed to have sent several thousand troops into Somalia to prop up the interim government. 

A week ago, a third round of peace negotiations between the interim government and the Islamists failed to start, after the Islamists demanded the withdrawal of Ethiopian troops from Somalia.  Ethiopia denies the allegations, saying it only has military advisors in Baidoa.

Ethiopia's arch rival in the region, Eritrea, is accused of shipping arms to Somali Islamists, prompting fears that a war between the Islamists and the government could ignite a regional conflict.