An Israeli woman and two of her children died from suffocation while sleeping in a room they sealed against a chemical missile attack.
Drills are carried out in schools
"The family sealed the room preparing it for war, and slept inside with a barbecue grill burning [for heat]," Sami Issa, mayor of the Israeli Arab village of Kafr Qassem, told Israel
Israel has begun extensive emergency preparations ahead of a possible United States-led war on Iraq, calling up reservists to operate anti-missile batteries.
Israeli citizens have been warned by the country's defence ministry that they should stockpile food and water and prepare themselves "for all possibilities".
Gas mask practice
School children practice in schools how to put on gas masks and evacuate the wounded.
"War is on the doorstep and the family was apparently over-anxious... [The room] was completely sealed. The barbecue was burning in the entrance and all the gas masks and chemical
protection kits were lying open," Mr Issa added.
Police reportedly found the mother and two children, aged 13 and 14, lying dead in the room.
Her husband and another child survived, reported Reuters news agency.
There are now 250,000 US forces in the Gulf
If the army ordered Israelis to seal rooms, families would only stay inside during a chemical attack.
They would also be told to turn off heating devices.
Israelis sealed rooms during the 1991 Gulf War, when Iraq fired 39 missiles with conventional warheads at Israel.
Leaflets have been distributed on how to seal rooms safely.