By Michael Kohn
BBC News, Ulan Bator
With deep rural roots, a strong leadership and an 87-year history, the Mongolian People's Revolutionary Party is the most powerful political force in this country.
Protests such as these are rare
But as of Wednesday, it was homeless.
The bulky, Communist-era headquarters of the MPRP was gutted by fire on Tuesday after a day of heavy rioting in the capital. Hour by hour, floor by floor, the flames climbed up into the building until there was nothing left to burn.
The incident started in the early afternoon when the Democratic Party, angered at apparently losing an election over the weekend, marched on the MPRP building.
Protesters overwhelmed a security force at the building and began smashing windows and destroying property.
Police in riot gear could do little to quell the violence. Tear gas and rubber bullets only temporarily dispersed the crowds before they returned in large numbers.
The protesters set the building on fire and then looted an alcohol shop on the first floor. Bottles of vodka were drunk and then used as weapons against the police.
The riot soon spread to the nearby Cultural Palace, home to a museum and theatre. The museum was looted and the building torched.
"This has been building for a long time. People are fed up with this party," said Dorjiin Khurelbaatar, a government worker who was on the streets. "When people are pushed, they will push back. Now we see the result."
As the MPRP building burned, another group set on a police station in a failed attempt to steal weapons. The melee left five dead. Over 300 people were injured, a third of them police.
Several news channels aired the violence live on television. Many families sat at home watching in horror as their normally peaceful city was consumed by chaos. Camera crews filmed shots being fired, a fire engine being attacked with bricks and people being beaten in the streets.
By 0300, the police had regained control of the city and were hauling rioters away in police vans. More than 700 were arrested.
While demonstrations are common practice in Mongolia, this level of violence is unknown. With just 2.6 million people, Mongolia is a small and largely homogenous country where everyone seems to know each other.
For many Mongolians, voting makes no difference
But in recent years the gap between rich and poor has grown.
While the new rich - made wealthy, in part, by the recent exploitation of the vast landscape for mineral wealth - drive expensive SUVs and dine in swanky foreign-owned restaurants, a third of the population struggles to survive on $2 a day.
Politicians and their business associates are assumed by many to be corrupt.
It seemed only a matter of time before the frustrations of the disenfranchised boiled over.
As for the accusations of vote rigging, such claims are nothing new in Mongolia. Complaints are lodged after every election, with fingers pointed at both parties. International observers have called last weekend's vote "mostly fair" and it appears that the results will stick.
The two major political players have rarely found common ground.
The MPRP is the former communist party that ruled Mongolia from 1921 to 1996. The Democrats are the young upstarts whose 1990 peaceful protests ushered in multi-party elections and a free market economy.
Control of the government has frequently changed hands as Mongolia's fickle electorate usually side with the opposition.
But, in fact, ideological differences between the two parties are few. The MPRP is a little left of centre, while the Democrats veer slightly to the right.
Both welcome foreign investment and have worked hard to lure Western mining companies into the country.
"The parties are the same," said Oidov Sanjaa, while surveying damage on the morning after the riots. "So doing the election over won't matter. The MPRP won and should do their job so the rest of us can get on with our lives."