Israel's annual national home front exercise began Sunday, as Hezbollah played up fears in Lebanon that the drill means a conflict might loom with its southern neighbor.

The exercise, "Turning Point 4," was due to last five days and be carried out in all parts of the country. During the first three days the drill was to involve the Israel Defense Forces' various command centers, the police, emergency services, ministries and other government offices.

The exercise, which is held annually in May, was to be broadened on Wednesday to include civilians, with a siren sounded at 11 A.M. throughout the country. Civilians were instructed to to seek cover in shelters or other secure areas.

Hezbollah's deputy head, Nabil Qaouk, said Friday that the Shi'ite organization had stepped up its alert status ahead of the "war game" being conducted on Sunday in Israel.

Qaouk said thousands of Hezbollah fighters will not take part in one of the stages of Lebanon's municipal elections today because they are preparing for the possible attack by Israel.

Meanwhile, Hezbollah Secretary General Hassan Nasrallah called on voters to pick the candidates put forth by the coalition between Hezbollah and Amal, another Shi'ite group.

Joining Hezbollah in its worries, Lebanese Prime Minister Saad Hariri said the Israeli exercise contradicts efforts to reach comprehensive peace in the region.

Hariri met with Egyptian President Hosni Mubarak in Cairo Saturday, ahead of his visit to Washington.

Israel has relayed messages to Arab states about the drill, stressing that it has no plans to launch an attack.

The exercise will focus this year on the ability of municipalities to respond to the launching of thousands of missiles and rockets on Israel. Most municipal authorities, where around 70 percent of the country's people live, will hold drills as part of the national effort, conducted by Home Front Command, the National Emergency Authority and the Defense Ministry.

Hundreds of police officers are scheduled to take part in the exercise; they will practice their three main tasks in the event of missile attacks: routine security, guiding traffic and maintaining order.

The police will be tested on how they respond to local emergencies while the force is spread out all over the country.

The main scenario for the police will be a strike on Be'er Sheva by missiles fitted with chemical warheads.

Another aspect of the drill will be surprise strikes at home front targets.

Many different elements of defense and rescue will be practiced. For the first time, for example, Israel will test its response to a blow to its computer and electronic-communications infrastructure after a cyber attack.

The authorities will also examine their ability to evacuate hundreds of thousands of civilians from areas hit by missile barrages or strikes by unconventional weapons.

The distribution of gas masks, something already underway over the past three months, will be expedited during the drill to include other parts of the country. Home Front Command will be tested on its ability to shift to emergency distribution on a national level.

Extensive participation by volunteers, nongovernment organizations and youth movements is expected to be part of the drill, especially in helping local authorities reach people and communities in distress or needing special assistance.