Things just keep getting worse for the US military in Yemen.

What was remaining of the US military presence in Yemen has been—or is in the process of—evacuating the region after attacks by both Shiite Houthi rebels and al-Qaeda forces caused a breakdown in security.

In their statement, the rebels described their coming offensive against security and military institutions loyal to President Abed Rabbo Mansour Hadi as a battle against extremists.

Their appeal came just minutes after Hadi gave a defiant speech challenging the Houthis, his first address broadcast to the public since fleeing Sanaa last month. He described the rebels’ rule in Sanaa and elsewhere as “a coup against constitutional legitimacy.”

The U.S. troops, including Special Forces commandos, were leaving the al-Annad air base near the southern city of al-Houta, Yemeni military and security officials said. Speaking on condition of anonymity as they weren’t authorized to discuss troop movements, the officials did not say whether the troops had left the country.

Some 100 American troops and Special Forces commandos are believed to be stationed there. U.S. officials declined immediate comment Saturday.

Fox News has more:

On Friday, two suicide bombing attacks on mosques in Sana’a killed over 100 people and wounded hundreds more. ISIS claimed credit for the attacks, and according to analysts the magnitude of these attacks is not consistent with something even Yemen’s lethal al-Qaeda cell would attempt, so the presence of a third force (read: ISIS) is probable:

Worshippers were attending noon prayers at the Badr and al-Hashoosh mosques in the capital when the attacks occurred, according to a report on the rebel-owned Al-Masirah TV channel. One witness at the al-Hashoosh mosque, located in Sanaa’s northern district, said that he was thrown some six feet away by the blast. Reuters cited medical sources in reporting the death toll, which was revised upward several times. The rebel-owned Al-Masirah TV channel said the casualty figures had reached 137 dead and 345 injured and reported that hospitals were urging citizens to donate blood. It also reported that a fifth suicide bomb attack on another mosque was foiled in the northern city of Saada — a Houthi stronghold.

Yemeni officials expect the death toll to rise dramatically in the next 24 hours overnight, possibly approaching 150.

“The heads, legs and arms of the dead people were scattered on the floor of the mosque,” Mohammed al-Ansi told The Associated Press, adding, “blood is running like a river.”

This comes just days after DoD officials admitted to having misplaced over $500 million in military supplies in aid previously sent to the region to support the now-deposed Hadi government. U.S. officials still cannot account for those supplies; the U.S. military evacuations have made it impossible for the intelligence community to track them.

Yemen is devolving. The only question is, which rebel group—al Qaeda, the Houthi, or ISIS, will spill enough blood to come out on top?