It remains unclear how many people were aboard the attacked boat in Mali. / Photo: Reuters

A passenger boat in the Niger River in northern Mali has been attacked by suspected extremists, the Malian army said on social media.

“At around 11am (1100 GMT), armed terrorist groups... attacked a Comanav boat” in the Gourma-Rharous area, it said on Thursday, referring to the ferry’s operator.

The boat, operating on an established route between cities along the river, was targeted by "three rockets," Comanav said separately.

There were no immediate details of any casualties.

The attack comes after an al-Qaeda-linked alliance, the Support Group for Islam and Muslims (GSIM), announced in August that it was blockading Timbuktu, the historic crossroads city of northern Mali.

The impoverished state has been struggling with insecurity since 2012, when a revolt led by ethnic Tuaregs erupted in the troubled north.

The insurgency was fanned by violent extremists, who three years later took their own campaign into central Mali, Niger and Burkina Faso, sending shockwaves across the Sahel.

AFP