By Will Ross
BBC News, Kampala
The Sudan People's Liberation Army says that a Ugandan rebel group has attacked and killed several of its fighters in the south of the country.
The LRA rebels are notorious for their brutality
An Anglican church says dozens of civilians have been killed by the same rebel group, the Lords Resistance Army.
The LRA has been terrorizing much of northern Uganda for the past 18 years, killing and abducting civilians, most of them children.
But their atrocities are also being carried out inside southern Sudan.
The SPLA says a large group of Ugandan rebels attacked its position near the Sudanese town of Torit, killing seven SPLA soldiers.
It says the LRA attacked on Friday morning and reports that civilians were also targeted by the rebel group, which has no clear political agenda.
Meanwhile the Anglican church in southern Sudan claims that the LRA rebels have been operating in small groups attacking civilians, principally to raid cattle.
The SPLA claims it lost seven soldiers in the LRA attack
Rev Paul Yugusuk of Lomega Anglican church says that over the past week at least 26 civilians have been killed.
Under an agreement between the Sudanese and Ugandan governments, Ugandan troops are allowed to pursue the LRA rebels inside southern Sudan, but within a limited area.
The Ugandan army claims the rebels are currently located near to Sudanese army positions and states that the Sudanese authorities could be doing more to pursue the LRA.
The Ugandan army spokesman on Saturday called on the Khartoum government to allow Ugandan troops to pursue the rebels further inside southern Sudan.
Some observers of the conflict claim that contrary to a signed agreement, the Sudanese army has maintained links with the LRA - the group it armed and trained for several years.
The Sudanese government denies this claim and says it is also on the offensive against the LRA rebels.