Reuters) - Al Shabaab militants on Sunday welcomed a reported incursion by hundreds of troops from neighbouring Ethiopia as a sign that Kenya's offensive against the Islamist rebels was failing.
The Kenyan military said warplanes backed by salvoes from warships off Somalia's coast destroyed an al Shabaab training camp in the Hola Wajerer/Lacta area of the Babade district.
An al Shabaab spokesman told Reuters the air strikes had landed in empty bush where they now had no bases.
The Kenyan assault on al Shabaab appeared to have slowed this week before the move by Ethiopia with Kenya blaming heavy rains and mud. Al Shabaab says guerrilla-style attacks have halted the advance.
Scores of Ethiopian military vehicles, ferrying troops and weapons, pushed at least 80 km (50 miles) into Somalia on Saturday, according to local residents and elders, crossing into the centre of the near-lawless country from Ethiopia and travelling through Kenya to reach its south.
Ethiopia on Sunday continued to publicly deny that any of its forces had entered its Horn of Africa neighbour.
Residents and elders witnessed the convoys and identified them to Reuters as Ethiopian. Al Shabaab also reported the presence of Ethiopian forces in several towns.
An Ethiopian Foreign Ministry spokesman said no decision had yet been made on whether to support the Kenyan army, which entered Somalia five weeks ago vowing to wipe out al Shabaab, who it blames for kidnapping and attacking tourists on its soil.
"We are glad to say Ethiopian troops are in the Guriel area. They have come because AMISOM and Kenya have failed in the fight against al Shabaab," Sheikh Abdiasis Abu Musab, an al Shabaab spokesman, told Reuters.
AMISOM is an African Union force of Ugandan and Burundian troops that has been largely responsible for keeping al Shabaab from ousting Somalia's internationally-backed but weak government.
It was unclear what the intentions of the Ethiopians were. Some local elders said they would fight al Shabaab and others that they will arm and train militias loyal to the government.
The last time Ethiopia entered Somalia was in December 2006, with tacit U.S. backing and at the invitation of a government that had lost control of the capital Mogadishu and large swathes of the country to another Islamist group.
The Ethiopians left Somalia in early 2009 after ousting that group but dogged by accusations that their presence, hugely unpopular with Somalis, was inspiring support for militias such as al Shabaab who were not as powerful at that time.
"Al Shabaab and the Ethiopians know each other. We made them pull out with their dead bodies two years ago. They plan to ease the burden on Kenya and AMISOM but we are really determined to fight them," Abu Musab said.
"Somalia is not a cool place to come and enjoy."
Sunday's air strike was the first of any note since the early days of Kenya's intervention.
In a day of skirmishes and counter-claims, Kenya denied a statement from al Shabaab that it had set a Kenyan navy vessel ablaze by firing rocket-propelled grenades from speed boats.
Somali government officials confirmed the sea engagement to Reuters and said the Kenyan military had hit one al Shabaab boat, which tallied with the rebel statement.
On land, Somali military officials said al Shabaab had ambushed a joint Kenyan-Somali patrol near Dhobley in the Lower Juba region.
"During the clashes we killed four al Shabaab militants and captured one of them alive," Abdikarim Ali Yusuf, a senior Somali military officer, told Reuters.
Al Shabaab said it killed eight Kenyans in the fight.
Police in the Dadaab refugee camp, a target of previous attacks by al Shabaab, said they had found an unexploded improvised explosive device on Sunday that had been hidden at the side of a road regularly used by United Nations aid workers.
Kenyan government ministers have shuttled around east Africa this week and gone to the Gulf to drum up political and financial support for a more coordinated campaign to rout the rebels in a country notoriously tough for foreign armies.
Some analysts say Ethiopia may want to take advantage of al Shabaab's withdrawal from Mogadishu in August to wipe out a group it sees as a threat to its stability.
The Ethiopian Foreign Ministry spokesman said a final decision on whether to join the assault against al Shabaab in some form would be taken next Friday.
"East African heads of state will meet on Friday to discuss ways of stabilising Somalia and one plan is to boost the number of AMISOM troops from both neighbouring countries and other African nations," Dina Mufti told Reuters.
When asked if Addis Ababa would agree to a request for troops he said: "Ethiopia supports Kenya's efforts and is very much part of the total initiative."
(Writing and additional reporting by Barry Malone; Additional reporting by Aaron Maasho in Addis Ababa, Sahra Abdi in Nairobi, Noor Ali and Daud Yussuf in Garrisa and Mohamed Ahmed in Mogadishu; Editing by Janet Lawrence)