Tens of thousands of Afghanistan's ethnic Hazaras marched on Monday through downtown Kabul, demanding the government reroute a planned power line through their poverty-stricken province so they can get more access to electricity. The massive protest reflected widespread dismay with the administration of President Ashraf Ghani.

Concerns that the protest could turn violent prompted the police to block off roads leading into the city's central commercial district. Stacked shipping containers prevented the marchers from reaching the presidential palace. A November rally by Hazaras protesting the beheadings of members of their minority by militants had turned violent.

Most of Kabul's shops were shuttered as armed police fanned out. Authorities restricted the protest organizers to a specific route that would bypass the palace.

The rally passed without major incidents but the protest underscored the political crisis facing Afghanistan as Ghani becomes increasingly isolated amid a stalled economy, rising unemployment, and an escalating Taliban insurgency, now in its 15th year.

Since taking office in 2014, Ghani has made little progress in keeping promises to bring peace and prosperity to the country. Instead, his administration seems to lurch from one crisis to another.

The U.S. Embassy closed its consular section and warned Americans to limit their movement within Kabul, cautioning in an emergency message that "even demonstrations intended to be peaceful can turn confrontational and escalate into violence." Other embassies, the U.N. compounds and non-government organizations were also locked down.

The blockade frustrated 40-year-old Muhammad Yaqoob who was trying to get his pregnant wife to hospital. "My wife is sick and I am trying to reach the hospital but I can't because everywhere they have blocked the roads," he said.

Daud Naji, a protest leader, said the Hazaras were demanding access to a planned multimillion-dollar regional electricity line. The so-called TUTAP line is backed by the Asian Development Bank with the involvement of Turkmenistan, Uzbekistan, Tajikistan, Afghanistan and Pakistan. The original plan routed the line through Bamiyan province, in the central highlands, where most of the country's Hazaras live. But that route was changed in 2013 by the previous Afghan government.

Leaders of Monday's rally say the rerouting is evidence of bias against the Hazara minority, which accounts for up to 15 percent of Afghanistan's estimated 30 million-strong population. They are considered the poorest of the country's ethnic groups, and often complain of discrimination.

Bamiyan is poverty stricken, though it is largely peaceful and has potential as a tourist destination. Hazaras, most of whom are Shiite Muslims, were especially persecuted during the extremist Sunni Taliban 1996-2001 regime.

Afghanistan is desperately short of power, with less than 40 percent of the population connected to the national grid, according to the World Bank. Almost 75 percent of electricity is imported.

Karim Khalili, a Hazara leader and a former Afghan vice president, spoke to the protesters from the back of a truck, saying the "people will never keep quiet when facing injustice." He called on Ghani and chief executive Abdullah Abdullah to change the decision on the power line.

As the march reached the Kabul Zoo, he urged the crowds to peacefully disperse until next time.

Some of Afghanistan's other ethnic minorities -- including ethnic Tajiks -- seem to be backing the Hazara demands. Political commentator Haroun Mir said that what started as an isolated grievance from one ethnic minority is gaining momentum as an umbrella issue for the many opponents of Ghani's unpopular government.

Abdul Malik, a 53-year-old Pashtun from southern Kandahar province, said he joined Monday's protest "to show unity."

"In the past 15 years very little has been done for Hazaras, and people need electricity in their homes," Malik said.

Ghani's office released a statement saying he is trying to resolve the issue through negotiations with community and protest leaders. Ghani and lawmakers had negotiated on Sunday with the protest organizers trying to postpone the march after Hazara lawmakers walked out of parliament the previous day over the power issue.

"The important point of these dialogues was to find means and resources to provide electricity to Bamiyan," the statement said, adding that Ghani had appointed a 12-member team to investigate the viability of rerouting the line through Bamiyan and ordered it to deliver its findings later this month.