BBC News - Afghan President Hamid Karzai has arrived in Pakistan for talks due to focus on tackling cross-border attacks.

During the two-day visit, Mr Karzai is expected to urge President Pervez Musharraf and other senior officials to crack down on Taleban rebels.

Islamabad denies it could do more to combat militants who use Pakistan as a base to launch attacks on Afghanistan.

Ahead of the visit, Pakistan freed more than 500 suspected illegal Afghan immigrants as a gesture of goodwill.

It is the fifth meeting between Presidents Karzai and Musharraf in Islamabad in four years.

The BBC's Mark Dummett in Kabul says that is seen as a sign of how important and tricky relations between them are.

'Inciting terror'

President Karzai flew into Chaklala air base near Islamabad before heading for talks with Gen Musharraf.

Earlier in the day, the Afghan president's spokesman said he would call for an end to terrorism, and ask Pakistan for action against Taleban rebels.

Afghan Foreign Minister Abdullah Abdullah said he was very concerned at continuing attacks in his country: "Especially recent suicidal attempts and the links these security incidents have to the other side of the border."

He told the BBC: "We hope we can sort them out with our neighbouring country Pakistan.

"Taleban leaders there are inciting terror and instigating terror and they are behind most of the incidents taking place in Afghanistan. So is al-Qaeda."

Suicide bombings

Pakistan supported the Taleban but changed its policy after a US-led invasion of Afghanistan in late 2001 removed the hard-liners from power.

Hundreds of Taleban and al-Qaeda militants were believed to have fled to Pakistan after they were toppled.

There have been a number of anti-Pakistan demonstrations in Afghanistan in recent weeks.

The Taleban has been blamed for an increase in violence in recent months, including a spate of suicide bombings.