By Ismail Taxta and Abdi Sheikh
MOGADISHU (Reuters) - Somalia's al Shabaab rebels called on Thursday for supporters in Kenya to carry out a major strike in retaliation for a 12-day military incursion by east Africa's powerhouse.
Kenya has sent soldiers and heavy weapons into southern Somalia to crush the al Qaeda-linked militants Nairobi blames for a string of kidnappings on Kenyan soil and frequent border incursions.
Kenyan units have advanced on several fronts with Somali government troops and allied militias toward al Shabaab strongholds and a fighter jet bombed its port city of Kismayu on Sunday.
"The time to ask Kenya to stop war has passed. The only option is to fight them. Kenya, you have started the war and so you have to face the consequences," Sheikh Muktar Robow Abu Mansoor, a top al Shabaab official, told a demonstration.
Kenyan military spokesman Emmanuel Chirchir told Reuters their forces clashed with al Shabaab fighters in southern Somalia, east of a town called Tabda, on Thursday and two wounded soldiers had been evacuated.
"There was action today between al Shabaab and our forces. We managed to kill nine al Shabaab," he said.
An al Shabaab spokesman, Sheikh Abdiasis Abu Musab, told Reuters his fighters had ambushed four Kenyan military vehicles near Tabda. He did not give details of any casualties.
The al Shabaab official urged sympathizers in Kenya to shun the grenade attacks that hit the capital Nairobi on Monday, killing one person and wounding 29. Police said on Thursday that all but six of the victims had now returned home.
"The Kenyan Mujahideen who were trained by Osama in Afghanistan, stop throwing grenades at buses. We need a huge blow against Kenya. Hand grenades hurled can harm them but we want huge blasts," he told hundreds of people gathered in Elasha, near Mogadishu.
Residents said al Shabaab had ordered them on Wednesday to close businesses and attend the anti-Kenyan rallies.
The two grenade attacks on a bar and a bus terminus in downtown Nairobi have spooked Kenyans and security has been beefed up in the capital at hotels, government buildings, restaurants, bars and shopping malls.
The blasts came two days after the U.S. embassy warned of an imminent attack. A Kenyan man has pleaded guilty to one of the attacks and being a member of al Shabaab.
MORE GRENADE ARRESTS
Kenya's Police Commissioner Mathew Iteere said two more people had been arrested over the attacks and were due to appear in court this week. He said the man who pleaded guilty went to Somalia in February and returned to Kenya in August.
The United Nations has warned that hundreds of Kenyan Muslims have been recruited by al Shabaab and that youth organizations have raised funds for the Somali militants.
A U.N. Monitoring Group report on Somalia published in July said al Shabaab had extensive funding, recruiting and training networks within Kenya.
Al Shabaab has yet to carry out a major strike in Kenya but has used suicide bombers to devastating effect in Somalia and Uganda -- whose troops are fighting the rebels in Mogadishu as part of an African Union force.
Twin suicide blasts in Kampala killed 79 people watching the soccer World Cup final last year and a truck bomb in Mogadishu killed more than 70 people earlier this month.
Gunmen also attacked a vehicle in northeastern Kenya on Thursday not far from the Somalia border, killing four government employees and wounding two guards, officials said.
Northeastern Provincial Commissioner James Ole Serian told Reuters the attackers were being pursued and another official said there were reports they were heading toward Somalia.
NO TALKS WITH SHABAAB
Kenya's southern neighbor Tanzania also issued a terrorism alert late on Wednesday following the Nairobi attacks.
"We have received threats," Robert Manumba, director of criminal investigations, told state TV. "Experience shows us that terrorism is an international crime. The al Shabaab group is composed of members from all east African countries."
Al Qaeda struck Kenya and Tanzania in 1998, killing hundreds of people in suicide bombings of the U.S. embassies there.
A diplomatic row between Somalia and Kenya over the incursion appeared to have been resolved. Somalia's president had cast doubt on the government's support for the Kenyan incursion on Monday.
But on Wednesday, the Somali government said while it had not agreed for Kenyan troops to cross the border, the prime minister would head a new committee to liaise with Nairobi.
"We support Kenya's operation inside Somalia because they support, train and provide other military support to our troops to defeat al Shabaab and we are very grateful to Kenya," Prime Minister Abdiweli Mohamed Ali told Reuters in an interview.
"But we have to understand one thing: Somalia has the lead, our military has the lead in all operations taking place inside Somalia," he said late on Wednesday.
The semi-autonomous northern Somali region of Puntland also said on Thursday it supported the Kenyan incursion.
Kenya has long watched its anarchic neighbor warily and its troops have made forays across the porous border with Somalia in the past, but this month's assault marks the first concerted push to drive the rebels away from the frontier.
Kenyan government spokesman Mutua stressed Kenya had no intention of occupying southern Somalia and would return once it had dismantled al Shabaab's networks. He also said Kenya would not negotiate with the militants.
(Additional reporting by Sahra Abdi, Mohamed Ahmed, Ibrahim Mohamed and Feisal Omar in Mogadishu; Noor Ali in Isiolo and Daud Yussuf in Garissa, Beatrice Gachenge, Aaron Maasho, Duncan Miriri and George Obulutsa in Nairobi; Fumbuka Ng'wanakilala in Dar es Salaam; Writing by David Clarke; Editing by Giles Elgood)