Four Kenyan education officials have been detained by suspected members of the Somali Islamist al-Shabab group after crossing the border.
Witnesses say the men entered Somalia to do some shopping when they were stopped by the Islamist militia which controls the region.
The group were held in the Somali town of Buulo Xaawo, Gedo region, 0.5km (0.3 miles) from Mandera town in Kenya.
Somalia officials have been reported as accusing the Kenyans of spying.
The BBC's Bashkash Jugosday in northern Kenya says the four officials and their driver were detained after straying over the border on foot.
There is generally a good relationship between the two towns on either side of the border but that could now turn sour, adds our reporter.
Many Somalis on the border depend on the Kenyan side for goods and services and send their children to be schooled there.
Buulo Xaawo district commissioner Ahmad Muhammad Burkus told Kenya's Standard newspaper the Kenyans had been found "moving suspiciously around the local police station".
He said they would be charged with being in the country without proper documentation.
"To us, they are suspicious looking and had intention to spy," he told the Standard.
Although the main border between the two countries is closed for security reasons, people are permitted to cross back and forth for trading.
The frontier was shut last year after two Kenyan nuns were abducted from the Kenyan border town of el-Wak.
Somalia has been without an effective central government since President Siad Barre was overthrown in 1991.
Al-Shabab now controls much of southern and central Somalia.