"an attack that raised concerns about Khartoum's ability to stop arms trafficking across its remote east." I think the right word is "willingness", not ability. Despite talk from the State Dept. about removing the country from the list of terror-supporting states, it remains knee-deep in terror. Its complicity in weapons trafficking makes that evident.
Seven Libyan soldiers killed in clashes with ISIS (Reuters)
from the article: Report: Hamas arms trafficker killed in Sudan air strike