In this story:

• American diplomat to head OSCE mission
• Sporadic fighting still reported
• KLA left out of process
• Related stories and sites

PRISTINA, Yugoslavia (CNN) -- An advance team from the Organization for Security and Cooperation in Europe will head into Kosovo Sunday, laying the groundwork for a 2,000-person international force that will monitor Yugoslavia's compliance with a promised military pullback in the disputed province.

The 13-person OSCE team, with members from eight countries, flew from Vienna to Belgrade Saturday and will head into Kosovo on Sunday to assess the requirements for the larger verification force, which is scheduled to be in place by October 27.

"We will go to all the probable sites where we expect to have people in place. We will look at the infrastructure that's available," said John Sandrock, an American who heads the advance team.

"We will report back to the OSCE permanent council on what we observe, what we see and what we feel we require in order to build this mission to the full strength that it's expected to reach," he said.

American diplomat to head OSCE mission

On Saturday, OSCE Chairman Bronislaw Geremek, the Polish foreign minister, announced that the full verification force would be headed by another American, William Graham Walker.

Walker, a career diplomat and former U.S. ambassador to El Salvador, has served as a U.N. special representative in Eastern Slavonia, a part of Croatia that was seized and later relinquished by ethnic Serbs after Croatia declared independence from Yugoslavia.

The unarmed OSCE verification force is part of an agreement reached Friday between Western powers and Yugoslav President Slobodan Milosevic to avert NATO military strikes on Yugoslavia.

Under the agreement, Milosevic has until October 27 to pull military forces from Kosovo, a majority-Albanian province of Serbia, one of the two republics that make up the Yugoslav federation. In February, Yugoslav troops and Serb police began a crackdown on ethnic Albanian separatists in Kosovo.

The OSCE force will monitor movements of Yugoslav forces, as well as assessing the humanitarian needs of ethnic Albanian Kosovars who have fled into the countryside to escape the crackdown.

As part of the verification process, the Yugoslavs also agreed to let NATO spy planes fly over Kosovo. Those flights began Saturday.

Sporadic fighting still reported

While NATO officials have reported large pullbacks of Yugoslav forces in recent days, there still are reports of sporadic fighting.

A house in the Kosovo village of Drogobilie was attacked Friday night, and some ethnic Albanians fled from their homes

The village of Drogobilie, southwest of the provincial capital, Pristina, came under attack Friday night from mortars, small arms and anti-aircraft guns. Some ethnic Albanians living there began preparing to leave.

On the outskirts of Podujevo, a Serb police post came under attack from three gunmen in camouflage, presumably ethnic Albanian guerrillas.

As Western powers continued to try to defuse the Kosovo crisis through negotiation, the main rebel group in the province, the Kosovo Liberation Army, placed a message in Albanian-language newspapers Saturday warning that it will punish anyone who dares to sign any agreement that obstructs the goal of outright independence.

KLA left out of process

The message was directed at moderate Albanian leaders, such a Ibrahim Rugova , who supports independence but rejects the KLA's use of violent struggle to achieve it.

KLA threatens punishment for anyone signing an agreement that obstructs the goal of Kosovo independence

Part of the agreement between Milosevic and the West calls for negotiations on Kosovo's future political status. The United States and some other Western governments support autonomy for the Albanians within the Yugoslav federation but oppose outright independence.

While Western powers consulted Rugova and other moderate Albanian leaders while negotiating with Milosevic, the KLA was not included. Zeton Surroi, publisher of an Albanian newspaper, says that may account for Saturday's threat from the rebel group.

"The context is that KLA is not included within this process, if there is a process going on. We would hear less of these kind of statements if there were mechanisms that would include them in," Surroi said.

Correspondent Richard Blystone and Reuters contributed to this report.