BBC News with Gaenor Howells

Kenyan soldiers have crossed the border into Somalia

in pursuit of

rebels from the Islamist group al-Shabab, who they blame for the recent kidnappings of several foreigners. An

eyewitness

told the BBC he'd seen about 25 armoured vehicles carrying Kenyan troops inside Somalia. Will Ross is following events from Nairobi.

We've been hearing from eyewitnesses inside Somalia saying that they've seen convoys of heavily armed military vehicles inside Somalia with Kenyan troops. There have also been helicopters seen inside Somalia. Certainly this is an operation that the Kenyan government wants to put on to show that they are serious about trying to tackle the problem of these recent kidnappings. Now the Kenyan government has blamed all four kidnappings on al-Shabab, even though there is no actual concrete proof that they were the work of al-Shabab. It's possible they were simply

bandits

carrying out kidnappings to get a ransom.

The former Socialist Party chief in France, Francois Hollande, has won the party's nomination to stand against President Nicolas Sarkozy in next year's election. The current Socialist leader Martine Aubry acknowledged defeat after today's second round of voting in a primary election. Hugh Schofield reports from Paris.

Martine Aubry has gone on radio and television in France conceding victory to Francois Hollande. He'd built up an

unassailable