It's quite common to think of Rwanda as being split into Hutus and Tutsis – but the truth is much more complicated. It might have been the case in 1994, when Tutsis united in self-defence. Today, though, the picture is different.

Tutsis are not a uniform group. They are split along lines that are crucial to the unrest unfolding in Rwanda now. The President, Paul Kagame, is from the Umwega clan, which has traditionally provided the Tutsi queen. When he became leader of the Rwandan Patriotic Front in the early 1990s, many of the generals, members of the Nyiginya clan that traditionally provided the king were uneasy – but they accepted it because of the threat they faced.

That was on the understanding that Kagame would return power to the Nyiginya – but he never had any intention of doing so. Now that his standing again at the forthcoming elections has made that clear, the Nyiginyas' patience has run out. They are so determined to be rid of Kagame that they have set up a rival political party and they are even willing to deal with the Hutus. Kagame is used to harassing the Hutus, but not other Tutsis. He is very frightened, very jittery and very aware that he is under threat.

Now someone is killing dissidents, and the people who threaten the regime. Within Rwanda, well-placed enemies of the President are saying that he must be got rid of quickly. If nothing happens before the elections, Kagame will impose himself again. But it is possible that his enemies will organise themselves and come back with violence. Kagame doesn't know who is loyal to him anymore; his enemies are lying low, but there could be an assassination attempt or a coup.

What happened in 1994 arose partly because of international ignorance over how serious the situation was. The world must be aware that things have the potential to get very bad once again. The UK is one of the countries best-placed to defuse the situation, because of the excellent relationship Tony Blair established with Kagame. Without an intervention, what comes next is unpredictable and extremely dangerous.

The author is head of Africa Inform International, a network of African journalists