MOGADISHU, Aug. 7 (Xinhua) -- Suspected Islamist insurgents on Thursday launched mortar attacks on the presidential residence and the airport in the southern Somali town of Baidoa, the seat of the transitional Somali parliament, witnesses said.

Six mortar rounds were fired on the presidential residence, where the Somali president Abdulahi Yusuf was not staying at the time as he is now in the capital Mogadishu.

Witnesses in Baidoa, the provincial capital of Bay region, 250 km southwest to Mogadishu, told Xinhua that two of the mortars landed inside the Presidential residence while two others hit the airport.

The Ethiopian troops responded with heavy artillery fire the sound of which could be heard throughout the city. I

Baidoa has been the seat of the parliament since the transitional government returned to the country following its formation in the Kenyan capital, Nairobi, in 2004. The transitional government relocated to Mogadishu in mid last year.

The city has recently been the target of insurgent attacks although it had been relatively calm compared to the capital, Mogadishu, which has been the scene of nearly daily clashes between insurgents and Ethiopian troops backing Somali government forces.

In July, insurgents launched mortar attacks on the Presidential residence and the airport in Baidoa. Several people, most of them civilians, were killed.

Last week the Somali transitional parliament voted for the deployment in Baidoa of newly trained police officers. The lawmakers said that the police should pacify and protect Baidoa where they are "much needed".