Reports of His Death Premature, Rebel Says : Liberia: A joking Prince Johnson meets with reporters after a rival group announced that it had killed him.

Rebel leader Prince Johnson met with reporters this afternoon and laughed off claims by rival rebels that he had been killed in an ambush.

Charles Taylor, Johnson’s rival in the yearlong battle to oust President Samuel K. Doe, claimed this morning his fighters had killed Johnson when he was surprised at a rubber plantation outside the capital, Monrovia.

A man identifying himself as Johnson earlier had called the British Broadcasting Corp. in London on a radiotelephone to deny he was dead, shouting into the phone, “Taylor’s a liar! I am alive!”

In Washington, the State Department said a “very reliable source” saw Johnson alive today.

The rebels hours earlier failed to show journalists Johnson’s body, as had been promised.

Taylor’s spokesman and defense minister, Tom Woewiyu, who announced Johnson’s death, said in an interview that if anyone talked with Johnson this afternoon, they were “talking with a corpse.”

Told that the U.S. State Department said Johnson was seen alive today, hours after the reported ambush, Woewiyu said, “They must have a different Johnson.”

At today’s State Department briefing, spokeswoman Margaret Tutweiler said, “We have a reliable source this morning that told us they have seen him today. . . . Alive. . . . They said they had a very reliable source that said they had seen him today.”

Earlier, a rebel commander identified as Oliver Varney led the ambush that supposedly cost Johnson his life, said rebel officers at their headquarters on the Firestone Rubber plantation about 37 miles southeast of Monrovia.

Woewiyu, spokesman for Taylor’s National Patriotic Front, earlier told reporters in Abidjan, in neighboring Ivory Coast, that Johnson had been killed on Bushrod Island while trying to leave Monrovia.

“Johnson was trying to get out of Monrovia when he ran into our forces,” Woewiyu said in a telephone interview.

Woewiyu had said Johnson’s body had been taken to NPF rebel headquarters and would be shown to reporters.

The two guerrilla leaders split three months ago in their violent war to oust Doe, and since then each has threatened to kill the other.

Johnson’s men had been holding much of Monrovia for several weeks after launching a surprise attack from a swamp north of the city. They caught Doe’s troops by surprise and took control of the city’s port area and also several residential districts.

The report of Johnson’s death came as an African peacekeeping force appeared to be meeting further delays.

Troops from Ghana, Nigeria, Guinea, Sierra Leone and Gambia have gathered in neighboring Sierra Leone, but there was no sign of an early departure.

Woewiyu said Taylor would be flying to Banjul, Gambia, this week to talk with Gambia President Sir Dawda Jawara, head of the African mediation committee trying to end the nearly eight-month civil war in Liberia.

This seemed likely to delay the arrival of the peacekeeping force.