SANAA, Yemen—Just weeks after a coup that ousted Yemen’s Western-backed government, the capital of Yemen is a city painted in green, mostly with spray paint.

Green tree trunks, green sidewalks, green walls and even a green Ford F-350 bearing the Houthi slogan, which includes the words “Death to America,” on each side of the iconic American truck, about 340 of which the Pentagon shipped to Yemen over the past few years.

The Houthis are now formally in control in Yemen, which is nearing economic collapse and civil war, but governing the country is another matter. The Houthis need a political deal with other parties, but U.N.-mediated talks have so far foundered, leaving the country in a state of chaos.

Sanaa today looks less like a city governed by new leaders, and more like a neighborhood taken over by a rival gang. The Houthis have placed stickers and placards on storefronts and walls around the city, an intimidation tactic aimed at its growing list of civilian and political opponents, including al-Qaida in the Arabian Peninsula, the Houthis’ bitter enemies.

But the most visible change in the capital is the prevalence of green, meant to honor the Islamic prophet’s birthday, which was celebrated Jan. 3 this year. The Houthis, who are members of the Zaydi Shiite sect, associate that color with the life and death of Mohammed.

Parts of Sanaa Old City are barely recognizable: the green, red and white lettering of Houthi slogans runs up and down the picturesque, stone-cut walls, and even a month after the January celebrations, green streamers still crisscross from building to building above gridlocked streets in Houthi-dominated pockets of the city.

“Yemenis never celebrated like this before,” said Ibrahim Al Kathiri, a dentistry student from Dhamar province. “It’s all the Houthis. This was all their idea.”

Some things haven’t changed, however; electricity and fuel are still in short supply, corruption is rampant and political violence continues.

Houthis—and what appear to be some underage teenagers—now man the city’s many checkpoints, dressed in a mix of military uniforms and tribal garb. The Houthis took over the capital and large parts of the country last fall, and after the government of then President Abdu Rabbu Mansour Hadi collapsed in late January, they seized control of virtually all of the state-run institutions.

They have yet to form a new government, however.

Yesterday, Mohammed Albasha, the longtime spokesman for Yemen’s embassy in Washington, D.C. announced on his Twitter feed that he would have to halt writing updates. He told The Intercept in an email that he was “on leave.”

Asked who was responding to press queries, a Yemeni embassy employee answering the phone said, “I don’t know.”

Meanwhile, the power vacuum in Sanaa continues and many of the foreign diplomats are evacuating. The U.S., British and French embassies all announced this week that they would be closing down operations and evacuating staff.

An official at Yemen’s Ministry of Foreign Affairs, who wished to remain anonymous due to fear of reprisal, said, “all embassies are empty or emptying in Sanaa. Who knows what’s next? We just have to wait. All we can do is wait,” he said.

– Cora Currier contributed to this article from Washington, D.C.

– Photo of Houthis manning a checkpoint in Sanaa: Casey L. Coombs