Witnesses said the remote-controlled device was aimed at the TFG Gedo region commissioner Mohamed Abdi Kalil, who was supposed to visit at a training facility in the police station.
"I saw blood all over the road and the bodies of three government soldiers," a witness told Somalia Report.
Five people, including two soldiers, were also wounded.
Abass Omar, director of Luuq hospital, told Somalia Report that the wounded were undergoing treatment for minor injuries.
Attempts to contact Islamist insurgent group Al Shabaab, which recently lost control of the town to TFG forces backed by moderate Islamist group Ahlu Sunna Waljama, were unsuccessful.
Kalil told Somalia Report that he had not been due to visit the station, and that the attack was aimed at claiming innocent lives.
The commissioner would confirm only that lives had been lost. TFG forces have begun operations around the area of the explosion in a search for those responsible.