In the dark, a young Yemeni soldier nervously scans the row of battered cars approaching his dusty checkpoint situated amid the volcanic mountains of Yemen's remote north.
"Get out of this place, it's dangerous," he shouts at passing drivers, pointing the beam of his flashlight into the shadowy palm trees by the roadside.
Since last summer, nearly 1,000 people have been killed as Yemen's Army battles Zaidi Shiite insurgents throughout the bleak, fossilized landscape of northern Yemen. Rebel clerics have denounced the government's ties with America and demanded an end to its gradual social and democratic reforms. In the government's place, radical cleric Badr Eddin al-Houthi wants to install an Islamic theocracy.
Fighting escalated March 28 after members of Mr. Houthi's rebel group Al Shabab al-Moumin, the Youthful Believers, attacked police in Saada, an isolated town in the north. Since then, The Associated Press estimates, 43 Yemeni troops and 37 militants have been killed, while local media put the total at nearly 300.
While government troops seem to have emerged victorious from the latest fighting - they overran the main rebel strongholds last Wednesday - the rebel leader and hundreds of his armed followers remain unaccounted for.
Many observers worry that the government may not be able to stamp out entirely al-Houthi's group, which aims to topple the country's embryonic democracy. They are also concerned that thousands of anti-Western rebels defeated in their tribal heartlands could attack foreigners and Western interests. Earlier this month the American and British embassies temporarily closed and warned their nationals to be on their guard against possible terrorist attacks. [Editor's note: The original version mistakenly stated that the embassies had warned their nationals to leave Yemen.]
"In Yemen, the two things which matter to people are tribes and religion," says Nadia al-Saqqaf, editor of the Yemen Times, an English-language newspaper. "And when someone combines the two, they can easily become a substantial political force."
This explosion of violence has been a devastating setback to the Yemeni government, which has tamed the threat from Al Qaeda and was beginning to enjoy the cautious return of tourists and foreign investors.
Without large oil reserves or any modern industry, Yemen is particularly vulnerable to terrorist attacks. The 2000 bombing of the USS Cole in Aden, Yemen's largest port, and the bombing of the French supertanker, the Limberg, in 2002, cost the country millions as shipping insurance premiums soared and many shipowners refused to dock in Yemen. It also frightened off tens of thousands of mainly European tourists who came to admire the country's spectacular landscape and ancient mud-brick cities.
Most Yemenis agree that the revolt stands little chance of success against the full might of the government, pointing out that the minority Zaidi sect makes up only a fifth of Yemen's population.
But unlike last summer, when the rebels made their doomed final stand in an isolated mountain stronghold, this time they are choosing to fight in cities and towns.
In addition, al-Houthi's views have increasingly gained traction far beyond the Zaidi sect.
Many Yemenis are angry that Yemen's fledgling democracy has failed to bring prosperity or accountability to their impoverished nation, while members of the government are seen as entrenching themselves in power to make fortunes through corruption.
"Just saying that the country is a democracy is not enough. We need to change this culture that says that violence is the solution to all our problems," says Abdul-Rahman al-Marwani, who runs an NGO that tries to arbitrate in tribal wars.
Part of the government's problem, however, is that many extreme religious groups refuse to operate within a democratic system that they see as invalid.
"Al-Houthi's followers think that the government does not follow sharia," says Ms. Saqqaf, the editor. "Therefore they say that they have a right to take up arms and fight the government." [Editor's note: The original version mistakenly referred to Saqqaf as "Mr."]
Yemen's struggle to reconcile democracy and popular fundamentalist readings of Islam has been long and violent. Last year, a three-month uprising by the Youthful Believers ended with the killing of the rebel leader Hussein al-Houthi.
The latest violence, led by his elderly father, may prove harder to crush as the rebels continue to carry out attacks on government forces across a large swath of northern Yemen.
The government-funded newspaper Al-Thowra reported that the Army is "convincing the rebels to surrender," although others say that the government is determined to annihilate them in a bid to deter any future uprisings.
"There are no grounds for negotiation with the rebels," says Dr. Ahmed al-Kibsi, a professor of politics at Sanaa University. "How can the government negotiate with a group whose only aim is to overthrow the government?"