UPDATE: 10 p.m. EDT -- The White House issued a statement from President Barack Obama on Thursday, the 22nd anniversary of the beginning of the Rwandan genocide.

On the anniversary date, Americans "stand with the people of Rwanda to commemorate the more than 800,000 men, women, and children whose lives were lost during 100 days of unspeakable violence. ... Today, even as the United States grieves with the Rwandan people, we are inspired by the progress Rwanda has made in moving beyond these horrible crimes and in building a more peaceful and prosperous future for its citizens."

Original story:

Rwandans commemorated Thursday the 22nd anniversary of the beginning of the 1994 genocide that exacerbated ethnic tensions and tore the African country apart. The 100-day massacre carried out from April 7 to mid-July was incited by the majority Hutu-led government and left hundreds of thousands of people dead, mostly among the minority Tutsi population. Here are six facts to know about one of the worst genocidal mass slaughters ever recorded.

1. Historically, Hutus and Tutsi were distinguished by their clan and social class, rather than by their ethnicity. Hutus were usually peasant farmers, while Tutsi were cattle owners. European colonialism fueled the divide, and Hutus were ultimately deemed the lesser ethnicity. With the help of Belgium colonizers, Tutsi forced Hutus to work, but denied them higher education and positions in government.

2. Hutu resentment of the Tutsi bubbled to the surface in the form of a social revolution by the 1950s. Hutus, forming the majority of the population, won preindependence elections in 1961, fueling ethnic tensions. When Rwanda gained full independence the following year, the fallen Tutsi elite fled the country to escape the ethnic conflict and violence that accompanied the new Hutu-led government.

3. Rwanda fell into civil war in 1990 after Tutsi rebels formed the Rwandan Patriotic Front (RPF). The warring sides signed the Arusha Accords in 1993 to create a power-sharing government. But the mysterious assassination of Rwanda’s President Juvénal Habyarimana and Burundi’s President Cyprien Ntaryamira, who were aboard an airplane that was shot down over the Rwandan capital Kigali on the night of April 6, 1994, triggered a full-scale genocide of the Tutsi population.

4. Within an hour of the downing of the plane, the presidential guard along with members of the Rwandan armed forces and Hutu militia groups set up roadblocks in Kigali to identify Tutsi and even moderate Hutus before brutally slaughtering them with impunity.

5. The mass killings spread like wildfire from the capital to the rest of the landlocked East African nation, with some 800,000 people killed during the next three months. By early July, the Tutsi-led RPF had taken control of much of the country, and more than 2 million people, almost all of them Hutus, fled Rwanda.

6. After declaring victory, the RPF set up a coalition government with Pasteur Bizimungu, a Hutu, as president and Paul Kagame, a Tutsi, as vice president and defense minister. Rwanda adopted a new constitution in 2003, which eliminated references to ethnicity and paved the way for new elections. Kagame was elected to a 10-year term as president. Currently 58 years old, the Rwandan leader will seek another seven years in power in 2017, after the approval of constitutional changes that would effectively allow him to stay in office until 2034.