As rebellion continues to unsettle Central Africa, Angolan rebel chief Jonas Savimbi and Zairean President Mobutu Sese Seko are clinging together in a desperate last stand as the war in Zaire threatens both men's futures.
For nearly three decades, the two men's fortunes have been linked, first as US proteges to fight communism and then after they were rejected by their sponsor when they refused to embrace democratic change.
Now Mr. Savimbi's UNITA guerrillas are helping Zaire's beleaguered government fight its own rebellion, contributing to the international spread of the conflict at the heart of Africa.
A security source close to UNITA (National Union for the Total Independence of Angola) says the movement has deployed 1,600 of its most battle-hardened men to help their ally next door.
Their aim is as much to ensure their own survival as to help Mr. Mobutu. Without Mobutu, UNITA will lose the vital supply routes that have enabled it to trade their diamonds for arms.
In addition, Savimbi is paying back Mobutu for the logistical support he has lent the Angolan rebel leader over the years.
"Savimbi could not be seen to be betraying his elder [Mobutu]," the source says. "He had no choice."
The source, who requested anonymity, says that initially some 200 UNITA special forces were deployed in Zaire's Shaba Province in December. Their numbers increased, and since mid-February some UNITA men have headed toward the eastern Zairean town of Kisangani.
The battle for Kisangani is deemed the most decisive since the uprising by Zairean rebels began five months ago, after Zaire revoked Tutsis' citizenship and tried to force them out of the country.
The source says the UNITA men were initially led by one of the movement's most senior generals, Abilio Numa. The general, however, was wounded in battle in Zaire and is believed to have died.
This report and the source's other assertions could not be independently confirmed, although regional analysts say they have heard reports that both UNITA and the Angolan government were lined up on either side of the Zairean conflict.
Norman Aphane, a political analyst with the Pretoria-based Africa Institute think tank, gives credence to reports he has heard that up to 6,000 UNITA men have amassed around Kamina in Shaba.
He describes Kamina as a well-equipped base that still has working infrastructure from the days when Washington used Mobutu and Savimbi as its proxies.
In return, despite official denials, the Angolan government is reportedly assisting the Zairean rebels, who want to end Mobutu's 31-year dictatorial reign. A regional military source cited an unconfirmed report that the Angolan government had supplied rebel leader Laurent-Desire Kabila's forces with several arms deliveries since mid-February, flying them from the Angolan air bases of Cabo Ledo and Catumbela.
Military sources in the region say that if the Zairean war spread close to the border with Angola, it would give the Angolan military the pretext it has long wanted to move into the northeastern diamond areas under UNITA control.
The Angolan participation is adding to a dangerous international mix of players in Zaire, while the United Nations and Western powers seem powerless to defuse the crisis.
Both sides of the conflict have relied on foreign help. The Zairean government has employed European mercenaries and Rwandan Hutu fighters. The rebel Alliance of Democratic Forces for the Liberation of Congo-Zaire has the backing of Rwanda and Burundi's Tutsi-led regimes and Rwanda's ally Uganda.
This alleged involvement by the two Angolan sides comes as that country hovers between war and peace. The international community has poured millions of dollars into Angola to bolster a November 1994 peace accord meant to end 20 years of civil war.
UNITA is stalling on joining a national unity government mandated under the UN-supervised peace agreement, and thousands of its men still have not been demobilized. No agreement has been reached with the government over yielding control of the vast diamond mines from which UNITA earns an estimated $500 million a year.
Foreign involvement in Kisangani's defense may partly explain why this is the first time the rebels have met resistance. So far they have captured one-sixth of Zaire's territory with remarkable ease.
The battle for the strategic river town, which has a large airport, is a major psychological turning point in the conflict.
If Mr. Kabila's forces take the town, as expected, the question will be what he would do next. Some analysts question whether he would be willing to open negotiations with the government over a five-point UN peace plan that includes withdrawal of foreign fighters and a regional conference.
The government says it would accept the plan. Kabila has expressed willingness to discuss the proposals - but without a cease-fire.
Having pushed into mineral-rich Shaba and poised on the edge of the rich diamond area, the rebels may want to press on. Kabila is flush with confidence, having built up what regional analysts estimate is a seasoned fighting force of 20,000 to 30,000 men.
A confrontation between UNITA and Kabila's rebels could lead to military stand-off, Mr. Aphane says. "Both forces are very disciplined and battle-hardened. It would be guerrillas versus guerrillas. This would mean ambushes and ambushes.
"I think the likelihood of taking Kamina would therefore be very small. UNITA still has a lot of arms stored in eastern Angola and some in Zaire itself," he says.