SANAA, Yemen — Yemen edged closer to civil war Wednesday as fighting spread to new parts of the country and government troops waged increasingly bloody street battles with opposition tribesmen for control of crucial areas in the capital.
The violence has transformed a largely peaceful uprising into a tribal conflict with no clear end in sight. The United States and Yemen’s Arab neighbors like Saudi Arabia, which have tried and failed to mediate a peaceful solution to the country’s political crisis, are reduced to sitting on the sidelines and pleading for restraint.
The bloodshed also threatens to unleash a humanitarian catastrophe as Yemen, already the poorest country in the Arab world, runs desperately low on gasoline, cooking oil and other basic supplies. It also raises fears that Islamic militants who use Yemen as a base will have even freer rein to operate.
The rising chaos has become a major concern for the White House, which announced Wednesday that John O. Brennan, President Barack Obama’s top counterterrorism adviser, would be traveling to Saudi Arabia and the United Arab Emirates this week to discuss “the deteriorating situation in Yemen.”
On Wednesday afternoon, tanks and armored vehicles could be seen rolling into Sanaa, the capital, from the south. The streets of Sanaa were largely empty as residents fled for the safety of surrounding villages. Exploding artillery shells and sporadic machine-gun fire could be heard across the city.
Despite his repeated public offers to step aside to ease the crisis, Yemen’s authoritarian president, Ali Abdullah Saleh, appeared to be gearing up for a major assault on the Ahmar family, the tribal rivals and political opposition leaders he has been battling for 10 days.
“This is the worst fighting we have seen since 1994,” when Yemen fought a two-month civil war, said one Yemeni official, who spoke on the condition of anonymity under diplomatic protocol. “And it’s the worst fighting in Sanaa since the civil war of the 1960s.”
Some estimates of the death toll in fighting late Tuesday and early Wednesday ranged as high as 41 on both sides. All told, at least 120 people have been killed since the violence began early last week. A brief cease-fire struck over the weekend collapsed Tuesday, with each side blaming the other.
In recent days, the government’s tenuous hold has slipped further outside the capital as tribal fighters and Islamist militants seized a major coastal town in the south and tribesmen took over critical checkpoints east of Sanaa. The southern city of Taiz remained in a state of lockdown, days after government forces and plainclothes gunmen opened fire on a vast crowd of peaceful protesters who had been holding a sit-in for months. Dozens of people were killed, according to witnesses and human rights groups, and the episode provoked condemnations from the United States and other countries.