The Bush administration responded angrily Friday to Hezbollah's (search) shelling of Israeli positions in a disputed Lebanese border region.

American diplomats told Lebanon and Syria that the administration was seriously concerned about what a U.S. official described as a "calculated and provocative escalation" by the extremist group and told the two Arab governments it was important to restrain further attacks.

Lebanon and Syria, which channels Iranian weapons to Hezbollah, were notified that it was in their best interest to maintain calm along the Israel-Lebanon border area and were advised there should be no violations of the line approved by the United Nations after Israeli troops withdrew from southern Lebanon.

Further, the administration told Syria and Lebanon the time has come for them to end their support for Hezbollah's terrorist operations, said the State Department's deputy spokesman, Philip T. Reeker.

The administration takes the position that Hezbollah openly condones suicide attacks against innocent civilians and is intent on perpetuating violence and blocking U.S. efforts to point the region toward peace.

The State Department urged Lebanon to deploy its armed forces in the southern part of the country and take away control of the area from Hezbollah.

The shelling was the first in eight months. Israel responded with airstrikes and artillery fire.

Hezbollah said in a statement that its attack was in retaliation for the killing of a Hezbollah security official Saturday south of Beirut. Hezbollah blamed Israel for killing Ali Hussein Saleh (search), who died when a bomb tore apart his car.

Hezbollah's Al-Manar television, quoting unnamed security sources, said the attack resulted in "a number of casualties" among Israeli soldiers, but Israeli military sources said there were none.