Kenyan forces on Thursday captured a pirates haven in Southern Somalia and were advancing towards the al Shabaab stronghold of Kismayu.
Ras Kamboni was seized by troops which entered Somalia through the Kiunga border point in Lamu.
"This avenue provides the Defence Forces with a vantage to clear al Shabaab and pirates on the Somali waters from Ras Kiamboni to Kismayu," military spokesman Major Emmanuel Chirchir said on Thursday.
The troops did not face any resistance, he added.
Ground troops moved in after air force jets had pounded targets in the town for several days.
Ras Kamboni has been a key haven, not just for pirates attacking ships in the Indian Ocean, but also had training camps for the al Qaeda-linked terror group.
It was also a key route through-which foreign jihadists were smuggled into Somalia to join al Shabaab.
Its capture came as President Kibaki explained why he had sent the military into Somalia.
Speaking during the Mashujaa Day (Heroes day) celebrations, the President praised soldiers involved in the incursion saying they were " the country's new heroes".
"We will defend our territorial integrity through all measures necessary to ensure peace and stability," the President said at Nyayo National Stadium.
After capturing Ras Kamboni, the troops in the south sector of the operation will now advance to the port city of Kismayu where they hope to link up with the others advancing through the central sector who are on the outskirts of Afmadow Town.
The troops in the Afmadow sector had been forced to scale down operations due to bad weather which made movement difficult.
The capture of Ras Kamboni is a major victory in the war against piracy which is one of the major sources of revenue for al Shabaab militants responsible for the insecurity in Somalia and the region.
Three other al Shabaab strongholds had already been overrun since the start of the offensive dubbed "Operation Linda Nchi (Kiswahili for Operation Protect the Nation). They area Dhobley, Tabda and Beles Qooqani, all in the central sector.
As the Kenyan troops battled the militants in southern Somalia, a joint operation by African Union and Transitional Federal Government forces captured the last al Shabaab stronghold in Mogadishu.
Daynile District, Northwestern of the Capital, was the only area still under the militants' control. It is a strategic corridor that connects Mogadishu to both Middle and Lower Shabelle regions.
Prime Minister Raila Odinga was the first to break the news of the fall of Ras Kamboni while addressing the nation during the Mashujaa Day celebrations.
"We are fighting the criminal group. Today (Thursday) we have taken over Ras Kamboni. We will fight them until we are secure," Mr Odinga said.
He said Kenya had a duty to protect its borders and to ensure the country remained stable and peaceful for the sake of the present and future generations. Major Chirchir said Afmadow Town was yet to fall.
The Kenya Navy was meanwhile patrolling the Indian Ocean waters near Somalia to deter pirates.