[12] On 21 September, as the Houthis took control of Sanaa, the Yemeni Army did not formally intervene, other than troops affiliated with General Ali Mohsen al-Ahmar and the Muslim Brotherhood-affiliated Al-Islah Party.

[15] The unrest took a dramatic turn in January 2015, when Houthi fighters seized control of the presidential palace and Hadi's residence in an effort to gain more influence over the government and the drafting of a new constitution.

In March 2015, the Saudi Arabian-led intervention in Yemen began with airstrikes and a naval blockade to restore Hadi's government to power.

On July 30, 2014, the Yemeni government announced an increase in fuel prices as part of reforms to subsidy programs, which aimed at unlocking foreign funding and easing pressure on the budget.

[23] Fuel subsidies were benefiting powerful political allies of Ali Abdullah Saleh, who were smuggling subsidized oil to neighboring markets where they would reap huge profits.

[24] In 2013, fuel subsidies cost the Yemeni government $3 billion, roughly 20 percent of state expenditure, according to a Finance Ministry statement carried by Yemen's official news agency.

The loan program would require the removal of these subsidies, but the IMF recommended gradual price adjustments and an information and communication campaign to prepare the public.

[23] The IMF and other international donors also emphasized the need to expand the social safety net and cash transfer payments to those who would be most affected by the price increases.

[23] The decision to lift fuel subsidies gave the Houthi movement, with its own axe to grind, the populist issue they needed to enter Sana'a and seize power.

On 21 September, as the Houthis took control of Sana'a, the Yemeni Army did not formally intervene as the moral guidance division of the armed forces declared its "support for the people's revolution".

[31] The troops that did fight the Houthis in an unsuccessful attempt to stop their advance were affiliated with General Ali Mohsen al-Ahmar and the conservative Sunni Al-Islah Party.

[15] The Houthis, along with several other Yemeni political groups, signed a deal entitled the Peace and Partnership Agreement which provided for the formation of a new unity government.

[36] Ahmad Awad bin Mubarak, the chief of staff to President Abdrabbuh Mansur Hadi, was initially named as Basindawa's successor on 7 October, but he declined the post under pressure from the Houthis.

[42] The Houthis continued to flex their muscle in December, blocking General Hussein Khairan from entering his office after Hadi appointed him army chief over their objections and accusing the president of "corruption".

[45] The group rejected the proposed draft of the constitution, which internally organized Yemen into six federal regions, while imposing presidential term limits, creating a bicameral legislature, and banning political parties based on religious or ethnic affiliation.

They accused Hadi of reneging on his promises regarding the draft constitution and arming al Qaeda, while government officials described the Houthi actions as a "move toward a coup".

President Hadi was inside the residence as it came under "heavy shelling" for a half-hour, but he was unharmed and protected by guards, according to Information Minister Nadia Al-Sakkaf.

The rebels roamed the streets of Sana'a on foot and in pickup trucks mounted with anti-aircraft guns, manned checkpoints across the city and near the prime minister's residence, and fortified their presence around other key buildings, including intelligence headquarters.

United Nations Secretary-General Ban Ki-moon expressed concern over the "deteriorating situation" in Yemen and urged all sides to cease hostilities.

[53] Local officials in the southern Yemeni port city of Aden responded to the Houthi takeover of the presidential palace and residence by closing its airport, seaport, and land crossings.

[66] Toward the end of January, several U.S.-based media outlets reported that the U.S. government had begun reaching out to the Houthis in an effort to establish a working relationship with the group, despite its official anti-American position.

[75] In an interview with The New York Times in Sana'a, senior Houthi official Saleh Ali al-Sammad rejected the characterization of his group's armed takeover as a coup.

A power plant and a liquefied petroleum bottling factory are also located in Marib, which provide cooking gas to a large portion of the population.

The landscape around Marib city is mostly flat desert plain, which exposes the Houthi ranks and makes fighting more difficult for their men who are used to battling in mountainous areas.

[77] In April 2015, United States National Security Council spokeswoman Bernadette Meehan remarked that "It remains our assessment that Iran does not exert command and control over the Houthis in Yemen".

[93] White House spokesman Josh Earnest said in January 2015 it was unclear whether Iran was "exerting command and control" over the Houthis, although he described the U.S. government as "concerned" about the reported ties between them.

Following allegations, it was suggested that Israel may have destroyed the MV Saviz, a suspected Islamic Revolutionary Guard Corps floating station used to collect intelligence and assist weapons trafficking into Yemen, according to Saudi sources.

[98][99] The London-based online news portal Middle East Eye, citing an unnamed "source close to the president", alleged that Saleh and his son Ahmed, Yemen's ambassador to the United Arab Emirates, received as much as $1 billion from the UAE to distribute to the Houthis in their campaign against Hadi's government.

[6] However, the next day, Hadi managed to leave his residence in Sana'a and travel to Aden, on the southern coast, where he declared he was still president under the Yemeni constitution and condemned what he called "the coup".