Afghanistan on alert one year on

An Afghan soldier looks on as a giant poster of Massood is hung in place at the sports stadium in Kabul

KABUL, Afghanistan -- Fighting has erupted in Afghanistan as the country's president heads to New York on the first anniversary of the assassination of a legendary resistance leader.

Clashes broke out in Khost on Sunday with at least 15 people reported dead and 51 wounded, just hours after a bomb exploded at a shop, wounding at least 10 people in the southeastern city.

The blast, who some suspect is the work of the Taliban or al Qaeda network, is the latest in a series of attacks in Afghanistan, including a car bomb in Kabul on Thursday that killed 26 people.(Attacks rock Afghanistan)

President Hamid Karzai, who survived an assassination attempt last week in Kandahar, left the country to join world leaders in New York, where he is due to attend a session of the U.N. general assembly. (Karzai profile)

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As part of a five-day trip, he will join the world body in commemorating the one-year anniversary of the terrorist attacks on the United States, where he is expected to visit ground zero at the World Trade Center.

In his first official visit to America, Karzai is expected to meet President George W. Bush to talk about the campaign against al Qaeda and Taliban holdouts, and the global efforts to rebuild his shattered country.

In the face of mounting civil violence, Karzai is likely to repeats calls to expand the International Security Assistance Force in Afghanistan, currently limited to the capital.

Kabul on alert

In the aftermath of Thursday's incidents, security in Kabul has been tightened ahead of events on Monday marking the first anniversary of the assassination of legendary anti-Taliban resistance leader Ahmad Shah Massoud, killed by suspected al Qaeda operatives.

After his death, the United States backed the Northern Alliance to ouster the hard-line Taliban, who supported the al Qeada network.

Massood was killed by two Arabs posing as television journalists, their camera packed with explosives. It is believed they were sent by Saudi-born militant Osama bin Laden to get rid of Massoud and help end the last pocket of resistance to their rule.(Afghanistan remembers Massood)

Massoud's death came two days before the attack on the World Trade Center, sparking a war in Afghanistan which brought a crushing end to the Taliban's rule.

Authorities are on watch for further violence on the first anniversary of the September 11 attacks on New York and Washington, blamed on al Qaeda and its leader, bin Laden.

International peacekeepers in Kabul have stepped up patrols and spot checks and local police were reinforced as last-minute preparations for the Massoud events were made.

Fragility

The blast was the most serious incident to hit Kabul since the government of Hamid Karzai took office earlier this year.

A giant portrait of the commander's face went up at Kabul's main sports stadium, where the hardline Islamic Taliban regime once carried out public executions, news agencies reported.

Thousands of people, including top government officials, will attend the commemoration at the stadium, while many more will travel to Massoud's shrine high on a hill amid stunning mountain peaks lining his Panjsher Valley stronghold.

The volatility in the eastern region, where U.S. forces have been hunting for the remnants of the ousted Taliban regime and al Qaeda network it sheltered, is a further reminder of the fragility of peace and stability in Afghanistan.

Karzai told reporters on a stopover in Frankfurt, Germany, that terrorism was being defeated but there was still a danger of further attacks anywhere in the world.

"They (terrorists) will of course try to have their last desperate acts," he said. "We will continue to fight them and to finish them completely to make the world safer for all of us."

Just this year alone, there have been several assassinations and failed assassinations of other officials of the new government. (Assassination attempt latest of several)