This latest smash-and-grab style attack is only the latest to take place in the conflict-ridden East African nation.
The militant group Al Shabab attacked a Somali town in a region near Kenya's border. At least seven Somali soldiers have been killed, the group and Somali officials said.
The group, based in Somalia, has lost control of most of the cities and towns which it held in recent years, yet retains a strong hold in rural areas.
Al Shabab regularly attacks Somali forces in its campaign to oust Somalia's Western-backed government. The group pulled their fighters out of El Wak overnight, residents said on Saturday.
"We captured five military vehicles and killed several members of the government forces," al Shabab's military operations spokesman Sheikh Abdiasis Abu Musab said, after the assault was launched on Friday afternoon.
Somali Major Mohamed Jimcale said that government forces had retreated to another town where there is a base for the African Union's AMISOM force.
"We lost at least 7 soldiers and two vehicles," he said.
Accounts and figures given by the officials and Al Shabab often vary.
Residents and government troops said Al Shabaab had cut off communications to El Wak before the attack.
Al Shabab fighters often stage raids and then withdraw before government forces have a chance to stage counter attacks.