Three suicide bombings struck checkpoints of Yemeni loyalist forces in Aden on Friday, killing 22 people, including 10 civilians, a security official said.
Two bombs went off simultaneously at separate checkpoints in Shaab district, on Aden's western outskirts, before gunmen attacked a nearby base of the Saudi-led military coalition, the official said.
Apache helicopters belonging to the coalition attacked positions of gunmen in the surrounding area as fighters attempted to advance toward the base.
A third explosive device planted in an ambulance was detonated at a checkpoint near Mansura, in central Aden, the official said.