Afghanistan's capital was in lockdown as tens of thousands of ethnic Hazaras marched through the streets calling on the government to re-route a powerline through their poverty-stricken province.
Amid concerns the massive protest could turn violent, roads leading into central Kabul's commercial district were blocked to all vehicle and foot traffic by police, who used stacked shipping containers to prevent the marchers reaching the presidential palace.
Most of the city's shops were shuttered and armed police units took up positions around the city. Authorities told protest organisers that the march would be confined to a specific route that would not take them near the presidential palace.
A November demonstration that followed the beheading of a number of Hazaras by insurgents turned violent.
The backing of other ethnic groups for the protest highlighted the political crisis facing Afghanistan, as President Ashraf Ghani becomes increasingly isolated amid a stalled economy, rising unemployment, and an escalating insurgency now in its 15th year.
The US embassy in Kabul closed its consular section and warned Americans to limit their movement within Kabul.
Other embassies, United Nations compounds and non-government organisations were also locked down.
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 demonstration have called the routing of the line away from their territory evidence of enduring bias against the Hazara minority.
Hazaras account 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.
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 the country's power is imported.
Karim Khalili, a Hazara leader and former vice president, told supporters from the back of a truck that the "people will never keep quiet when facing injustice.
"Again I want call on Dr Ashraf Ghani and [chief executive] Dr Abdullah Abdullah to change the decision - don't you think a change of mind regarding the electricity line would be better?" he shouted to the crowd that had stopped near the Kabul Zoo in the west of the city.
As leaders of other ethnic groups backed the Hazaras' so-called Movement of Light, political commentator Haroun Mir said what started as an isolated grievance from an ethnic minority has gained momentum and grown into an umbrella issue for the many opponents of Ghani's unpopular government.
Ghani's office released a statement saying he had worked tirelessly in recent weeks to resolve the issue through negotiations with community and protest leaders.
The statement said Ghani had appointed a 12-member team to investigate the viability of rerouting the line through Bamiyan and suspended work on the project until the commission reported its findings later this month.