(CNN) -- At least eight mortar rounds rained down on the Somali capital of Mogadishu late Wednesday, security officials and witnesses said.
The mortar attacks, the second barrage to rattle the capital in the past week, were scattered across several parts of Mogadishu, including the presidential palace and the national theater, the officials and witnesses said.
Reports of casualties and damage were not immediately available, security officials said.
Mohamud Shiekh, a witness near the national theater, said that at least one mortar landed near presidential palace.
"It was really scary. It's reminiscent of the 2010 chaos," he said.
A barrage of mortar fire from Islamic extremists pummeled parts of the Somali capital for two nights last week, near the presidential palace and other government buildings. Some civilian homes were struck.
At least 13 civilians were injured in last week's attacks.
Al-Shabaab, the Somali-based group with ties to al Qaeda, claimed responsibility for last week's attacks.
In recent years, U.S. officials had considered Al-Shabaab to be diminished in strength, but after the attack at the Westgate shopping mall in Kenya last year, officials have worried that the group has demonstrated a renewed capability.
Somali national army and African Union peacekeepers are in final preparations for major offensive against Al-Shabaab, according to President Hassan Sheikh Mohamud.
The radical Islamist group, which controls parts of Somalia, has said it aims to turn the country into a fundamentalist Islamist state.