JERUSALEM —  With conflict in Iraq nearing, the Israeli military called up reservists in anti-aircraft units, and Israeli citizens sealed rooms in their homes to ward off chemicals and germs.

However, Israeli experts and officials said the probability of an Iraqi strike at Israel in response to a U.S.-led assault was low, and preparations for a chemical or biological attack were just precautions.

The military completed its mobilization of reserve soldiers on Tuesday, military sources said, commenting on media reports that more than 10,000 soldiers received emergency callup notices for anti-aircraft units and the Home Front Command, which deals with civilian matters in wartime.

The Israeli daily Haaretz reported Wednesday that the Israeli air force had raised its alert level, and warplanes were patrolling Israel's air space 24 hours a day. Besides the potential threat of Iraqi missiles, Israel is also preparing for the possibility that Iraq might try to send a poison-laden plane toward Israel.

Israel also has two types of anti-missile systems in place -- the short-range Patriot and longer-range Arrow, developed jointly with the United States since the 1991 Gulf War, when earlier model Patriots failed to bring down any of the 39 Scud missiles launched by Iraq. All had conventional warheads.

In 1991, Iraqi strikes followed threats to retaliate against Israel for a U.S.-led assault. This time, Iraq has said repeatedly that it does not have weaponry that can reach Israel, also denying that it has chemical or biological weapons. The United States has rejected the Iraqi assurances.

Shmuel Arad, a reserve army general, wrote in the Yediot Ahronot newspaper Web site that the chances of an Iraqi missile strike on Israel are low. "Israel is better prepared than ever, both in defensive and offensive capabilities," he wrote, adding, "Israel's population should follow the developments calmly, even with a smile and a bit of humor."

Echoing Israeli government views, Arad said the war with Iraq "is not our war," but Israel had a clear interest in the removal of Saddam Hussein from power.

The Israeli government cranked up its home-front readiness when the army instructed citizens to seal windows and doors in a room in their houses. A day earlier, the military told people to make sure they had the necessary equipment -- nylon sheeting and packing tape, along with food and water to store in the rooms.

But many Israelis waited until Tuesday to buy supplies, and others disregarded the instructions, taking the assessments of a low probability of an Iraqi attack at face value.