US envoy Richard Holbrooke prepared for talks on Friday in Afghanistan aimed at stepping up the struggle against a Taliban-led insurgency that the top US intelligence chief said was expanding in scope.
   
His arrival in the country late on Thursday came a day after triple Taliban attacks on government offices killed 26 people and left eight attackers dead - three of them in suicide blasts.

Some analysts suggested the coordinated attacks in Kabul may have been an attempt by the Taliban to overshadow Holbrooke's trip and underline their own strength despite military and political pressure on their Pakistan bases.

In a separate incident on Thursday, five Afghan children were killed and a number of civilians injured in a firefight involving Australian troops and insurgents in Afghanistan's southern Uruzgan province, the military said on Friday.
   
The defence department said Australian soldiers were conducting "clearance operations" in compounds on Thursday when they were fired on by Taliban rebels and returned fire.

  
US embassy spokesman Mark Stroh confirmed Holbrooke's arrival.
   
Details of his itinerary were not released, although Holbrooke is expected to visit a range of international and Afghan authorities.
   
His tour - he flew in from Pakistan and will travel on to India - is part of a major focus on this region by the new US administration under President Barack Obama.
   
Obama, who has pledged to make Afghanistan the main front in the struggle against terrorism, is expected to decide shortly whether to send more troops there.
   
But the scale of the task was highlighted by retired admiral Dennis Blair, the new US director of national intelligence.
   
In an annual threat assessment to Congress, he said the Taliban-dominated insurgency had expanded in scope over the past year - moving into previously peaceful areas around Kabul and elsewhere.
   
His report said the security situation had worsened in many eastern areas, as well as the south and northwest, and predicted insurgents would likely make a concerted effort to disrupt presidential elections due later this year.
   
It said the Kabul government's inability to develop honest, effective and loyal institutions at local and district level "erodes its popular legitimacy and increases the influence of local warlords and the Taliban."
   
Corruption has also "exceeded culturally tolerable levels," it added.
   
Blair's report noted similar problems in neighbouring Pakistan, notably in the restive tribal border areas which have come to be regarded as safe havens for Al-Qaeda and Taliban militants.
   
A US-led coalition ousted the Taliban from power in late 2001, but rampant unrest and the fragility of the Kabul government continue to lock down tens of thousands of international troops here.
   
Top military officials have suggested 15-30,000 extra US soldiers may head to the south of Afghanistan, where Taliban violence is worst and a number of districts have fallen out of government control.
   
Extra troops are also seen as vital for securing presidential elections - only the second in Afghanistan's history - due on August 20, already delayed for three months largely because of security problems.
   
Afghan President Hamid Karzai has in turn stepped up pressure over civilian casualties from mainly US military operations against insurgents, calling for the "war on terror" to be directed at militant sanctuaries in Pakistan and not Afghanistan.
   
Holbrooke, who did not speak publicly during his three days of meetings in Pakistan, said before his visit that he was coming to listen and learn before reporting back to Obama and US Secretary of State Hillary Clinton.
   
One positive development Blair reported in his assessment threat was that Al-Qaeda was now "less capable and effective" than a year ago after a wave of strikes in Pakistan's tribal areas that had killed key commanders.
   
However, he said it was still planning attacks on the West and is believed to view Europe as a "viable launching point."