Israel has apparently decided to adopt a "zero tolerance" stance regarding any attempts to infiltrate the border from Lebanon, The Jerusalem Post has learned.

Lebanese observers said that this marks a drastic change in Israel's policy towards people approaching the border from Lebanon and is a specific warning to the civilian population and to the new government of Beirut.

"It looks like this is a very firm approach by the IDF, and we have no reason to believe anything to the contrary," said a senior UN source.

The UN source said that he had been informed by Israel that the IDF would now adopt a policy of "zero tolerance" to any crossing of the blue line, the UN delineated withdrawal line.

It is the most serious statement of intention ever made by the IDF since the withdrawal from Lebanon in May 2000, in full compliance with UN Security Council Resolution 425. There was no comment on Wednesday from security officials on the matter.

Lebanese media reported on Wednesday that a stern warning had been issued by Israel to the Lebanese authorities and civilian population that anyone who crossed the international border faces warning shots that, if not heeded, would be followed by directed fire.

"We are not relaying messages from Israel to Lebanese civilians," senior UN sources told The Jerusalem Post on Wednesday. "On our own initiative, we are undertaking a preventative measure by warning that Lebanese civilians could be shot and, as a result, wounded or even killed if they cross the blue line," the sources told the Post.

Israel's warning, which was reported in full by Lebanese newspapers on Wednesday, follows the infiltration by a high-caliber Hezbollah squad in the Mount Dov region a week ago.

During the infiltration, Hezbollah laid down a heavy barrage of mortar fire on IDF outposts in the Mount Dov region in which Cpl. Uzi Peretz, 19, of Beersheba was killed and four other soldiers were wounded.

A Hezbollah gunman was also killed in the exchanges and his body was recovered from the field by soldiers. Another Hezbollah gunman was reported to have been wounded in the firing and the third member of the squad apparently escaped unhurt.

They reportedly managed to escape IDF patrols and flee back to Lebanon, leaving behind all their equipment that included sophisticated night vision sights, video and still cameras, as well as weapons, clothing and sufficient food to keep them in the field for several days.

OC Northern Command Maj.-Gen. Benny Gantz said their activities and equipment indicated that they were part of an overall plan to kidnap soldiers. Hezbollah, according to military sources, has decided to try and kidnap soldiers in the belief that such actions would have the support of the Lebanese people.

This follows the exchange deal in which Lebanese and Palestinians held by Israel were released in exchange for the return of Elhanan Tannenbaum and the bodies of three IDF soldiers killed in a Hezbollah ambush in the Mount Dov region in October 2000.

Military sources made it clear on Wednesday that the IDF would do everything necessary to avoid a repetition of those events, especially in light of the abortive kidnapping attempt by Hezbollah last week.