The Fog of War
Most of you should remember Muhammad al-'Awfi's - the former Guantanamo detainee and one time military commander of AQAP - confessions back in March of this year when he alleged that al-Qaeda and the Huthis had an alliance to strike at the Yemeni government. The confessions, as I mentioned at the time, were rather poorly staged, but the substance if not the form have continued. The Yemeni government has even extended its own domestic axis of evil to included the Southern Movement.
Now things are starting to come full circle, as the Huthis are allegeding that the Yemeni government is using al-Qaeda fighters against their own fighters in and around Sa'dah. This comes just as the Yemeni government is claiming that it has arrested five Iranians on a boat with weapons that were destined for the Huthis.
So if one believes the Yemeni government then the Huthis are allied with: al-Qaeda, Iran, Hezbullah, Shi'a in Bahrain and throughout the Middle East who are supporting their co-coreligionists in Yemen as well as Iraqi Shi'a in the Iraqi government.
If one believes the Huthis then the Yemeni government is allied with: al-Qaeda, Saudi Arabia, former Iraqi officers loyal to Saddam Hussein (who are allegedly flying bombing raids) and the US.
(Various other smaller actors have allegedly played a role on both sides - but the ones above are the main ones.)