Lord's Resistance Army (LRA) rebels have opened fire in a market place in the northern Ugandan town of Apac, killing 10 people.
"The rebels armed with rifles attacked the market at Barrio at 1200GMT on Wednesday and killed 10 people and injured many more," Reuters news agency quoted a police officer saying by telephone from Apac
district, 250 kilometres north of the capital Kampala.
It was the first attack by the LRA in the Apac area this month.
In a separate incident, LRA rebels attacked a refugee camp further north in Gulu district, killing three people, including a local militiaman.
The LRA rebels are led by Joseph Kony and based in the southern part of Sudan, northern Uganda and, of late, in eastern Uganda. They have fought the government since 1988.
Thousands of civilians have been killed and more than a million others displaced by the fighting in northern Uganda alone.
In an unusual move, the rebels retreated after opening fire in Apac - normally they loot and abduct children.
Humanitarian organisations say that about 20,000 children have been abducted by the rebels over the last five years, with many taken into LRA bases in southern Sudan, where they the boys are trained as child soldiers while the girls are used as sex slaves.
More than 14,000 Ugandan troops backed by tanks, artillery
and helicopter gunships were deployed in the north last year to
fight the LRA, but have so far failed to defeat them.
The LRA abducts children for use as fighters and sex slaves
The Ugandan Government blames Sudan for supporting the LRA; Sudan in turn claims that Uganda supports the rebel Sudan People's Liberation Army (SPLA) which operates from southern Sudan.
The Sudanese Government denies supporting the rebels.
The two countries signed protocols earlier this month in which Sudan extended for another month a deal permitting Ugandan troops to pursue LRA rebels into Sudan.
Tuesday saw Uganda's Defence Minister, Amama Mbabazi, say that Sudan had made a fresh promise to stop supporting the Lord's Resistance Army rebels.
Mr Mbabazi and the head of military intelligence met President Hassan el-Bashir of Sudan over the weekend and delivered a message from Ugandan President Yoweri Museveni.
"We delivered the message that despite the standing protocols between our countries against LRA support, credible threats of Sudan army officers arming Kony continue," Mr Mbabazi told Ugandan MPs on Tuesday.