Somali gunmen kidnapped three foreign aid workers on Saturday in a raid on a Kenyan border town, then went back over the porous border into the Horn of Africa nation, rebels and residents said.
Cross-border raids are fairly common in the remote region, but usually involve cattle rustlers or gangs of robbers preying on business people in both countries. Ill-funded Kenyan security forces can do little to police the vast, impoverished area.
Somalia's militant al Shabaab group, which denied involvement, vowed to track down the captors who took the three workers from Mandera town, straddling the Kenya-Somali border.
"The authorities in Mandera (in Kenya) told us that those aid workers had been kidnapped. We're now going to run after them," said Sheikh Osman, an al Shabaab member in the neighbouring district in Somalia.
Al Shabaab said that the kidnappers were moving deeper inside Somalia and were sighted in the Berdale district of the Bay region in south-central Somalia.
"We have confirmed from a driver on the road that the kidnappers' land cruiser is on the road nearby, and we are going to find it," al Shabaab member Ali Abdikadir told Reuters from Berdale.
No group has claimed responsibility, but al Shabaab blamed some people in another Islamist rebel group, Hizbul Islam -- which controls nearby Luq town -- for the attack. Hizbul Islam was not immediately available for comment.
"Luq administration facilitated the kidnappers to use it as a safe haven, and well-known individuals masterminded this kidnapping," Sheikh Osman told local media.
The two groups are usually allies in their fight against the government, but differences and disputes have been emerging. Somalia's varied insurgent alliances are often further complicated by clan loyalties and local disputes.
WAKE UP TO GUN SHOTS
The aid organisation has asked its name and the nationalities of the hostages not be released. In the past, most foreigners kidnapped have been released after a ransom payment.
Residents in Mandera said an unknown number of assailants entered the town early on Saturday and seized the three.
"I got up to gun shots, and it was over in a very short time. In fact, there had been no resistance at all except from the guard whom they shot in the head and he is at the hospital now," resident Abdi Mohamed told Reuters by telephone.
Suspicion of kidnappings usually falls on clan militias or insurgents. Seizures are usually of Somalis, sometimes of foreigners and increasingly of ship crews off the coast.
Somali pirates released a German-owned ship on Saturday after receiving a $1.8 million ransom.
On Tuesday, two French security officials were kidnapped in the Somali capital Mogadishu and eventually handed over to al Qaeda-linked al Shabaab rebels.
Somalia's government and a 4,300-strong African Union force have been unable to wrest control of rebel strongholds in Mogadishu and other parts of the country despite international support and training.
A two-year insurgency there has killed at least 18,000 people, according to a local rights group.