Fighters from the Al-Qaeda-linked terrorist group have reportedly driven government-allied forces out of Tardo in Somalia

Al-Qaeda-linked Al-Shabaab terrorists have captured the town of Tardo in Somalia's central Hiiran region and are pushing forward with a longstanding offensive that has displaced thousands across the East African nation, Reuters reported, citing a Somali military official.

The fragile central government in Mogadishu has struggled to fight off Al-Shabaab despite foreign military support. An African Union peacekeeping force drove the militant group out of the capital in 2011, but it still controls large swaths of land in Somalia's southern and central regions, carrying out sporadic bombings and gun attacks on civilians and military infrastructure.

Major Mohamed Abdullahi told the outlet that Tardo, a strategic town which connects larger urban centers, fell on Sunday after fighters from the terrorist group drove out government-allied clan forces.

"The group is advancing to other areas after the fall of Tardo," Abdullahi said, adding that Somali forces and local clan fighters known as Macwiisleey are preparing a counteroffensive.

On Monday, the Somali National Intelligence and Security Agency said it conducted joint operations in Hiiran with international partners, killing at least 15 insurgents, with five others severely wounded.

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Al-Shabaab has waged an insurgency in Somalia since 2007, seeking to overthrow the fragile federal government and establish its own rule based on a hardline interpretation of Sharia law.

In February, US President Donald Trump announced he had ordered precision airstrikes in Somalia targeting an unnamed senior Islamic State (IS, formerly ISIS) attack planner and other militants. As of May, US Africa Command estimates that American forces have carried out 25 airstrikes against IS and Al-Shabaab in the Horn of Africa nation since Trump took office in January. The Pentagon claimed the strikes destroyed terrorist hideouts in Somalia's northeastern Bari region and killed multiple militants.

Despite the operations, terrorists targeted the convoy of Somali President Hassan Sheikh Mohamud in a bomb attack while he was traveling through Mogadishu in March. At least ten people were killed in May when a suicide bomber detonated explosives outside a military base in the capital. A day earlier, senior army commander Colonel Abdirahmaan Hujaale was assassinated in the Hiiran region.