OVER the last few weeks, dark, menacing, rainy-season storm clouds have hung over Eastern Congo like some ominous portent of things to come.

With its skyline dominated by the brooding presence of the still-active volcano known as Nyiragongo, the city of Goma sits on the shores of the giant Lake Kivu.

Sometimes it is jokingly referred to as the Congolese Riviera. But the city's charms are skin deep. Not least because memories still linger here of the 1994 genocide just over the border in neighbouring Rwanda that spilled over into Congo and in part laid down the roots of the latest conflict from which this long-suffering region is once again reeling.

Goma is no stranger to war and in what is now known as the Democratic Republic of Congo (DRC), history has a nasty habit of repeating itself.

The last time I was here was in 2008 as Tutsi rebels of the National Congress for the Defence of the People (CNDP), led by former Congolese army general Laurent Nkunda, advanced to within a few miles of the city with the aim of capturing it.

Standing in Nkunda's way at the time was a rag-tag collection of disgruntled Congolese soldiers and troops of the UN peacekeeping mission to the country. Today the situation is much the same.

Back in 2009, many of the roads leading out of Goma were littered with the debris, death and suffering of a war that had few frontlines as such. Every so often one would come across the bodies of rebel and government soldiers or civilians caught in the crossfire.

For some reason I recall the sight of one corpse, a man, his mouth wide open as if in a contorted, grotesque grin. He had lost his left hand, the limb perhaps hacked off or eaten by animals from the bush.

Congo's wars are marked by a particular savagery. Women, especially, suffer at the hands of rebel militia and government soldiers, many of whom regard rape and horrific sexual violence as routine.

A little over three weeks ago I returned to Goma to see for myself the latest escalating humanitarian crisis in North Kivu Province.

Another mainly Tutsi rebel group known as the March 23 Movement (M23), comprised in part of mutineers from the Congolese Army and led by former CNDP commander Bosco Ntaganda, has marched on Goma, entering the city last week. Ntaganda, called "the Terminator", is wanted by the International Criminal Court on charges of war crimes and crimes against humanity.

In the days leading up to M23's taking of the city I travelled along the pot-holed road that leads to the strategically important town of Sake, 17 miles west of Goma.

"If the rebels take Sake, the gateway is open to Goma," was how one man summed up the significance of this town that sits at a crucial east-west road junction.

On the way I was to witness some of the first of the tens of thousands of people displaced by the fighting in the last week alone. In total, half a million Congolese are now affected by the war between M23 and government forces as well as myriad other armed tribal and militia groups that terrorise civilians in the region.

Those civilians I saw on the road between Goma and Sake, like the many that have followed in recent days, were bent double carrying bedding, stoves and a few other precious belongings. Not for the first time in many years these people have been forced through no fault of their own to move without food, water or shelter and in fear of their lives.

Along the route, they must negotiate makeshift checkpoints thrown up by frequently vicious rebel and government gunmen.

Inside Sake, just before the fall of Goma, the Congolese Army had clearly intended to make a stand.

In villages beside the roads leading to the town I saw soldiers with Kalashnikov assault rifles and rocket-propelled grenade launchers who had effectively embedded themselves inside these civilian communities, sleeping in the makeshift huts and eating the little food that most ordinary people here survive on. To refuse the needs of those with guns in Congo is to provoke trouble and perhaps run the risk of death.

Over the last few days the situation around Sake and elsewhere has deteriorated rapidly. The M23 rebels, widely thought to be backed by Rwanda, are also on the move south from Goma through the hills towards the lakeside town of Minova, in a strategic position on the road to Bukavu, the capital of neighbouring South Kivu province. One rebel spokesman said they had come within seven miles of Bukavu before halting. Their push, they say, could take them all the way to the country's capital, Kinshasa, enabling them to "liberate" the rest of this vast central African nation, even if it is 1600 kilometres away.

In Kinshasa, authorities have banned protests, citing the need to keep order in what Congo's chief of police, Charles Bisengimana, called an "undeclared state of war".

Back on the eastern frontline, failed attempts at a counter- offensive last week forced government troops to pull back to Minova, leaving a trail of corpses and equipment in their wake.

In a desperate effort yesterday to halt the rebel advance, government troops reinforced their positions south of Goma, as African leaders met in the Ugandan capital, Kampala, to try to end the deepening crisis.

Fractured government forces were said by an army spokesman to be digging in on the shores of Lake Kivu in a bid to regain territory lost last week as the rebels pushed out of Goma.

"Our objective is to retake territory we've lost," said Colonel Olivier Hamuli.

"We are going to defend Minova, but we'll also try to push back the rebels," he insisted, adding that troop reinforcements were being sent to the frontlines.

With this intensification and spread of fighting comes, of course, the threat of a humanitarian catastrophe like the one that engulfed Eastern Congo in 2008. But with increasing reports of summary executions, widespread rape and large-scale recruitment of child soldiers, aid agencies are hampered by the escalating violence.

International humanitarian organisation Concern Worldwide, along with other aid agencies, has called for stronger protection of civilians and safe access to deliver humanitarian assistance.

"The rapidly deteriorating security situation has greatly impeded Concern's work with those who were already displaced since this most recent conflict began in April," said Concern's overseas director Paul O'Brien, who has just returned from North Kivu. On Friday, thousands of residents fled Sake on foot heading east toward Goma, where tens of thousands of people are estimated to already be sheltering in camps.

There are "bodies lining the road" leading south from Sake, said Thierry Goffeau, a senior official with the medical agency Medecins Sans Frontieres/Doctors Without Borders.

Two wars that shook DRC between 1996 and 1997 and then again from 1998 to 2002 both began in this same Kivu region, with Rwanda and Uganda playing active or behind-the-scenes roles in much of the fighting.

A report released on Wednesday by the UN Group of Experts said that both Rwanda and Uganda have "co-operated to support the creation and expansion of the political branch of M23 and have consistently advocated on behalf of the rebels."

The report's release, just one day after the violent takeover of Goma, is sure to increase pressure on the international community to confront the two eastern African countries over their role in neighbouring Congo's conflict.

Since 1998, more than three million people are estimated to have died from combat, disease and hunger and 1.6 million have been left homeless in DRC in a conflict that is the most lethal since the second world war.

The days ahead will likely see yet more of this scarcely believable hardship, suffering and violence. Congo is once again staring into the abyss of all-out war.