Israel is warning that it would strike government targets in Syria and Lebanon if these countries do not restrain the militant Islamic group Hezbollah. The warning follows recent violence between Hezbollah and Israeli troops on the border with Lebanon.

Israel's deputy defense minister, Ze'ev Boim, warns that if Hezbollah continues to escalate violence along the Israeli border with Lebanon, then the fighting will spread to other parts of Lebanon and Syria.

His comments follow reaction to the killing last week of one Israeli soldier and the wounding of six others in attacks by the Hezbollah, which is based in southern Lebanon.

Mr. Boim says it is clear that Israel is not only dealing with the Hezbollah, which is listed by the State Department as a terrorist organization. He says Syria is supplying the militant group with money and weapons, and is the main power broker in Lebanon, controlling activities inside that country.

Mr. Boim says that if Hezbollah is allowed to continue attacking Israel then it will be, in his words, catastrophic for Syria and Lebanon.

On Wednesday, Hezbollah gunners fired anti-aircraft shells over the western Galilee region of Israel in what the organization claimed was retaliation for violations of Lebanese airspace by Israeli warplanes earlier that day. Israeli warplanes then struck at suspected Hezbollah positions in southern Lebanon.

On Thursday, Israeli troops thwarted an apparent attempt by Hezbollah fighters to cross into the Golan region, an area that Israel seized from Syria during the 1967 Middle East war.

Israeli troops patrolling the area the following day said they were fired upon by Hezbollah gunners using mortars and anti-tank missiles.

Meanwhile, the Israeli government denied media reports that it is in possession of a bone fragment of Israeli airman, Captain Ron Arad, who disappeared over Lebanon in 1986.

The reports said the bone fragment had been passed on by the Hezbollah, via German mediators, as part of efforts by the organization to secure a new agreement on the release of more Arab prisoners held by Israel.