The Democratic Republic of Congo's east is one of Africa's flashpoints, gripped by militia violence which has claimed more than 1,000 lives in a matter of months and caused more than half a million people to flee their homes.

The government in Kinshasa has in the past accused neighbouring countries of seeking to destabilise it. These governments have in turn said that DR Congo, a vast country the size of western continental Europe, is a haven for groups that oppose them.

Since April "we have recorded eight incursions by South Sudanese soldiers" into the territory of Aru, in the eastern province of Ituri, local civil society chairman Innocent Magudhe told AFP.

The latest incursion took place on Wednesday in Kokwa, located on the border with South Sudan, he said.

During the incursions South Sudanese soldiers "burn houses, loot the property of the population" by taking cows and motorcycles, in an area where Congolese soldiers are in reduced numbers, according to Magudhe.

- Persistent rumours -

Further south in neighbouring North Kivu and South Kivu provinces, the presence of the Rwandan and Burundian armies "was noted" during the month of April, a monitoring group called the Kivu Security Tracker (KST) said in its monthly report published Friday.

In North Kivu, the Rwandan army "participated in the hunt for Rwandan Hutu rebels of the Democratic Forces for the Liberation of Rwanda (FDLR), jointly with the Congolese army", KST said.

FDLR's leaders were involved in Rwanda's 1994 genocide that killed about 800,000 people -- mainly Tutsis.

The Burundian army intervened in South Kivu "to hunt down Burundian rebels, including the Resistance for the Rule of Law with the support of other local groups," it said.

"It seems that the objective was to guard against Burundian rebellions in South Kivu, especially before the May 20 presidential election" in Burundi, according to the monitoring group.

Persistent rumours of incursions by Rwandan soldiers on DR Congo soil have never been confirmed by the Kinshasa authorities.

At the end of April, Rwandan President Paul Kagame denied them at a news conference in Kigali.

The KST report also recorded clashes between the Congolese military and fighters from various armed groups active in North Kivu and South Kivu provinces, and an increase in violence against civilians.

"After a particularly mild month of March, the atrocities have returned to a sadly usual level: 85 killings of civilians by armed actors were recorded in April," according to the KST.

DR Congo's east was the theatre of two major wars, which ran from 1996-1997 and from 1998-2003, the second of which eventually involved nine countries and two dozen armed groups.

Millions died from the fighting, disease or malnutrition.