Al Qaeda in the Arabian Peninsula has taken advantage of the chaos in Yemen to gain territory, U.S. Secretary of Defense Ash Carter said Wednesday.

The instability in Yemen, where Iranian-backed Houthis have seized control of San’a and several provinces, has created a vacuum in which the Houthis, AQAP and other groups are competing for control, Mr. Carter said at a news conference in Tokyo.

He said the U.S. sees AQAP “making direct gains on the ground there as they try to take territory, seize territory in these battle lines, which involve actually several factions.” He added, “We are observing AQAP participating in that kind of fighting.” […]