* One Kenyan officer wounded in ambush
* Al Shabaab controls much of territory across border
(Adds quotes, details)
By Noor Ali
ISIOLO, Kenya, July 20 (Reuters) - Kenyan security forces clashed along the border on Tuesday with gunmen from the Somali rebel group that was behind deadly suicide bombings in Uganda this month, an official and residents said.
Both Kenya and Somalia's al Shabaab militia were reported to be sending reinforcements to the area, although similar border skirmishes in the past have not escalated into wider fighting.
Wilson Murungi, commissioner of the Kenyan border district of Lagdera, said al Shabaab gunmen ambushed a Kenyan border patrol and wounded one officer. He said a team had been sent to beef up security and investigate the incident.
"The attack was not a raid inside (Kenya). Our officers were attacked as they conducted a normal patrol. The militias fired at them on the other side of the border," Murungi told Reuters.
Residents near the Liboi border post in Kenya said there was a fierce exchange of fire between the two sides.
Al Shabaab, a hardline rebel group with links to al Qaeda, controls much of southern Somalia bordering northeastern Kenya and is fighting to topple the Western-backed government in the Horn of Africa nation.
Al Shabaab is regarded as a patchwork of networks including foreigners who favour al Qaeda-style global attacks as well as more nationalistic Somalis who want to impose their own harsh version of Islamic sharia law at home.
The Uganda bombings were the first al Shabaab strike outside Somalia, although there have been fears for some time in Kenya that the violence could spill over the long and porous border between the two countries.
Washington, which supports the Somali government and an African Union peacekeeping force in the capital Mogadishu, is keen to prevent senior foreign militants within al Shabaab from promoting an al Qaeda-type approach among middle tier fighters.
A clan elder in the Somali town of Dhobley on the other side of the frontier told Reuters that two dead al Shabaab fighters were brought there and buried on Tuesday.
"Here in Dhobley, al Shabaab are calling people to jihad against Kenya and deploying more militias to the border. Local people fear new fighting between the two sides," said elder Yusuf Ali Mohamed.
Kenya tightened security along its border with Somalia in February in anticipation of a government offensive which has yet to materialise. There were fears that Somali rebels might try and enter Kenya if attacked at home.
Kenya has twice been hit by al-Qaeda linked attacks and while it cannot take part in the African Union peacekeeping in Somalia because it is a neighbour, the government has pledged to do what it can to prevent the chaos next door spreading. (Additional reporting by Sahra Abdi and Humphrey Malalo in Nairobi; Editing by David Clarke and Jon Hemming)