Following sporadic raids against each other over the summer, al Qaeda in the Arabian Peninsula (AQAP) and the Islamic State in Yemen (IS-Y) have engaged in open warfare in Yemen’s Al Bayda since late August.

Since Aug. 27, the two groups have claimed a combined 29 attacks against each other in Al Bayda’s Qayfa region. This region has seen fierce fighting between the two in the past and has historically been a critical area for AQAP.

Both sides have said its men have taken and retaken territory, launched improvised explosive device (IED) attacks against one another, sniped opposing militants and attacked various positions via mortars and rockets.

AQAP has been responsible for the majority of claims (23), while IS-Y has mainly reported its men repelling AQAP assaults. The heaviest days of fighting have so far been Sept. 1 and Sept. 9, in which the majority of the claims were published.

Islamic State photo reports of the fighting appear to back up the claims that its men have repelled AQAP assaults. Many of the photos detail dead bodies and captured weapons.

The renewed fighting has mainly taken place in Qayfa area and its surrounding villages, including Al Hamida, Al Zoub, Sarar, Awaja, Liqah, Al Najd, and Abu Ghayth. FDD’s Long War Journal has attempted to map out the fighting above.

Interestingly, AQAP has accused IS-Y of working with Houthi militants, which have indeed historically operated in the Qayfa region, against its forces. In return, IS-Y has accused AQAP of working with Yemeni military forces against its men.

This latter accusation repeated an earlier claim made in the Islamic State’s weekly Al Naba newsletter last week. In that issue, the unnamed emir of IS-Y’s Al Bayda Province said that “AQAP coordinates with the army of the tyrant (Mansour) Hadi.”

The emir then stated that AQAP has been weak against the Houthis and have not actively targeted the insurgent movement.

That said, the two jihadist groups have reported attacks against both the Houthis and the UAE-backed Security Belt forces in recent weeks.

The latest spate of open conflict between AQAP and IS-Y is the heaviest fighting between the two since April. In that fighting, which also occurred in Qayfa, dozens of fighters on both sides were killed.

Prior to April, the two engaged in sporadic outbursts of conflict and propaganda videos since the the overall infighting between AQAP and IS-Y began in the Qayfa region in July 2018. Both sides also engaged in taking prisoners during this period, a practice that has continued into recent months.

In the years prior, the two groups operated within an apparatus of uneasy cohabitation amid various propaganda campaigns. This degradation largely tracks with how the relationship between al Qaeda and the Islamic State elsewhere has played out, such as in Syria and Somalia.

While it is unknown how long this current spate will last, it is clear that both al Qaeda and the Islamic State are still in open warfare inside Yemen.

Caleb Weiss is a contributor to FDD's Long War Journal.

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