Foreigners, Belgian Troops Fly Out of Shattered Rwanda : Africa: Mortar shells fall on airport as they board plane. Thousands of refugees stream into neighboring countries.

Mortar shells slammed into Kigali airport Thursday, threatening attempts by foreigners and Belgian troops to escape Rwanda’s slide into gruesome anarchy.

As a tide of tribal slaughter raged into a second week, a total of 10 mortar rounds hit taxiways and the perimeter of the international airport while the last of 400 Belgian troops were pulling out.

Three of the rounds screamed in while what Belgian officers said was the last planeload of 40 foreign passport-holders and journalists to leave the capital was boarding.

More than 20,000 people are estimated to have died since fighting broke out between the army and the rebel Rwandan Patriotic Front a week ago. The fighting and the mayhem in Kigali are deeply rooted in the decades-old feud between the majority Hutu and minority Tutsi ethnic groups.

Many of the Rwandans wept during the flight to Nairobi, mourning slain relatives and reliving the horror of their escape from the city. Others simply stared in silence, too shocked to speak.

“More and more of the civilian population armed with machetes are ruling the streets, and the army can’t control them,” said Phillippe Gaillard of the International Committee of the Red Cross.

In Geneva, the International Federation of Red Cross and Red Crescent Societies said that at least 30 Rwandan Red Cross workers were killed in the fighting in Rwanda and that the toll could rise.

Heavy fighting between the army and RPF rebels broke out at dawn Thursday and raged on for much of the day despite heavy showers.

Belgium was the only Western country with forces still in the remote central African state, a former Belgian colony.

Aid agencies said tens of thousands of refugees were fleeing into neighboring Tanzania, Burundi, Uganda and Zaire.

The International Rescue Committee humanitarian organization reported an eight-mile-long column of people streaming out of Kigali.

About a third of the capital’s 300,000 people are believed to have fled.

Amnesty International accused the United Nations and Western countries of not doing enough to protect Rwandans.