MONROVIA, LIBERIA, JUNE 3 -- Dozens of government soldiers streamed out of Monrovia today on the road to neighboring Sierra Leone and others evacuated their families amid fears of a rebel attack on the capital.

Rebels led by Charles Taylor, who seeks to overthrow President Samuel Doe, have moved a force of up to 3,500 fighters to within 30 miles of the capital. No change was evident at the battlefront today, but Doe's soldiers were reported Saturday to be retreating from the front toward Monrovia.

North of the capital, dozens of soldiers were seen leaving with their families, trying to get rides in taxis and vans heading for Sierra Leone.

At Spriggs Payne Airfield in the capital, government soldiers were trying to put hundreds of family members onto aircraft headed for Grand Gedeh County, an area still controlled by the government and a stronghold of Doe's Krahn tribe.

Also fearful of rebel reprisals and trying to leave the city were members of the Mandingo tribe. The rebels have accused the Mandingos, primarily affluent business people, of supporting the Krahn tribe. The rebels, who are mostly members of the Gio and Mano tribes, have reacted in the past to alleged army atrocities against civilians of their two tribes by attacking Krahn and Mandingo civilians.

Diplomats said it was possible but unlikely that Doe's elite anti-terrorist unit was preparing a last stand at the executive mansion on the Atlantic coast.

But diplomats said more than half of the 2,000-strong Israeli-trained forces had been ferried by aircraft to Grand Gedeh in the past week, and there was speculation that Doe may be preparing to flee the country.

A high desertion rate has helped reduce the ranks of the Liberian army, which was believed to number 4,500 at the beginning of the five-month-old conflict, to roughly 3,000 to 4,000 fighters, about as many as the rebels.

Doe announced Friday that he would not run in scheduled 1991 elections, in an apparent bid to persuade the rebels to go to the negotiating table and to convince outside powers, especially the United States, that he is worth saving. The United States is Liberia's main foreign supporter.

Of particular importance to the U.S. government are CIA installations in Liberia that gather and disseminate intelligence for the region, as well as for parts of Latin America and Europe.

Liberia also has a powerful Omega marine transmitter responsible for guiding all U.S. shipping in the Atlantic Ocean, and is considered one of the five most important U.S. naval transmission bases in the world.