May 19, 2009, 13:57 GMT
Mogadishu - Ethiopian troops have re-entered Somalia as hardline Islamist insurgents push to topple the weak transitional government, witnesses said Tuesday.
Witnesses told Radio Garowe that Ethiopian troops and trucks crossed the border and set up a roadblock at the Kala-Beyr junction - a crossroads that connects southern Somalia to the semi-autonomous region of Puntland and Ethiopia.
Ethiopian officials denied the reports.
Ethiopia pulled its forces out in January, two years after it invaded to help kick out the Islamic Courts Union (ICU), an Islamist regime that controlled Mogadishu for six months.
However, Ethiopia said it reserved the right to send forces back in if if felt its security was threatened.
Somali insurgents have launched a major offensive against the government of President Sheikh Sharif Sheikh Ahmed, and the last 12 days have seen fierce fighting in Mogadishu and other parts of the country.
Main insurgent group al-Shabaab on Sunday took control of the strategic town of Jowhar, 90 kilometres north of Mogadishu, while allied group Hizbul Islam on Monday seized another town near Mogadishu.
Over 150 people, many of them civilians, have been killed in the fighting and hundreds more have been injured. Tens of thousands of civilians have also fled Mogadishu.
Sheik Sharif's government, propped up by 4,300 African Union peacekeepers from Uganda and Burundi, only controls small sections of Mogadishu, while the insurgents hold sway across much of Southern and Central Somalia.
The government received a boost on Sunday, however, when a leader of a faction of Hizbul Islam defected to the government side with his militia.
Sheikh Sharif has implemented sharia law and has been attempting to build bridges with the warring groups. However, the militants say he is too close to the West.
The president, who worked alongside many of the insurgents when the ICU briefly ruled Somalia, came to power earlier this year as part of a Western-backed peace process.
The insurgency, which was prompted by Ethiopia's invasion, has claimed the lives of around 16,000 people, mainly civilians.
The resultant insecurity has helped feed an explosion of piracy in the Gulf of Aden.
Somalia has been embroiled in chaos since the 1991 ouster of dictator Mohamed Siad Barre, and is widely regarded as a failed state.
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