After months of ferocious fighting, Afghan army units battling the Taliban in southern Helmand province are facing major restructuring and leadership changes, with several key commanders being replaced, a U.S. military official said Monday, January 25, the Associated Press reports.

U.S. Army Brig. Gen. Wilson Shoffner, the head of public affairs for the U.S.-NATO mission, told The Associated Press that the Afghan army corps in Helmand is now being "rebuilt" and that senior officers are being replaced.

The reasons for the changes in the Afghan army's 215 Maiwand Corps "are a combination of incompetence, corruption and ineffectiveness," Shoffner said. The corps' commander has been replaced, along with "some brigade commanders and some key corps staff up to full colonel level," he said.

Helmand is a strategic region for the Taliban, as it borders Pakistan. It grows large quantities of opium, used to produce most of the world's heroin. The harvest is worth up to $3 billion a year, and helps fund the insurgency.

The Afghan Defense Ministry confirmed the changes in Helmand. It said veteran army Gen. Moheen Faqiri was appointed to lead the corps and took over two months ago.

Gen. Dawlat Waziri, the ministry's spokesman, said brigade commanders have also been rotated out and replaced. "Soon, other army units will have new commanders there," Waziri said.