After Juvenal Habyarimana and Cyprien Ntaryamira died in a plane shot down by a rocket, the Interahamwe and their proponents (large proportion of the Hutus) were told by a state radio station announcing that May 5, 1994 is the day to clear out Tutsis in the capital of Rwanda, Kigali.  They ungrudgingly went ahead and massacred about 800,000 Rwandans between April and July.  Furthermore, they used agriculture tools such as machetes to do the deeds.  It was because they were void of modern tools.  Most of the estimated two million refugees fleeing to Burundi, Tanzania, and Zaire (now Democratic Republic of the Congo) were Hutus trying to evade the Rwandan Patriotic Front (RPF).  [1]

In July 1994, RPF soldiers arrived in Kigali as they were feared for their capability of placing a very disciplined guerrilla militia into the battlefield.  The Rwandan army was no match for them as they kept on losing occupied land to them.  Also, a provisional government was formed by the RPF.  It was no until next month that the whole country was close to be entirely controlled by them.  [1]

The RPF, mostly led by Tutsis, right from the start made a committed to racial equality.  The first cabinet of Rwanda accomplished the feat by having congressional members reflecting the numerical balance in the country. Sixteen of its members were Hutus, six were Tutsis. Ethnic identity cards were abolished by the government.However, the concept of getting rid of racism was very much difficult to achieve. [1]

Zaire became a breeding ground for people willing to help out Hutu Power's cause. There was an estimated 1.1 million Rwandans in the refugee camps set up in Zaire. Most of the perople were Hutus. There were also members of the Interahamwe that participated the genocide fled over the borders to avoid RPF.These refugees were able to "establish brutal control. There was general consensus that everyone in the camp should be identified and separated to take back some control that the Interahamwe gained.  The bigger problem was that neither Zaire nor any international force was willing to commit to the task.  This caused the refugees to stay exiled from Rwanda while the RPF government was eager to take them back.  [1]

It was not until late 1996 that people were slowly going back to Rwanda.  Obviously some of the members of the Interahamwe were still among refugees and returned home.  Yet, the more notorious criminals stayed in Zaire and ended up arming and training for violent sorties across the border.  [1]

Reference:

[1]   http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ad24#3299