The Home Front Command will on Sunday begin testing a text-message warning system to individual cell phones with alerts about impending missile attacks or other emergencies, sources from the Israel Defense Forces said. Officials expect the system to be operational by next month.

From Sunday to Thursday, from 8 A.M. to 6 P.M., cell-phone owners subscribing to Cellcom, Pelephone and Orange will receive a message in Hebrew saying "Home Front, testing cell-phone warning system." The Home Front Command has also agreed in principle to work with Hot Mobile subscribers.

The system will be tested in the Ramle area on Sunday and Monday, and on Tuesday in Tel Aviv-Jaffa, Haifa, Acre, Nahariya, Carmiel, Safed, Kfar Sava, Yehud, Netanya, Ashdod, Ashkelon, Kiryat Gat, Sderot and Netivot. On Wednesday it will be tested in Rishon Letzion, Rehovot, Yavne, Gedera, Mazkeret Batya, Sde Boker, Mitzpe Ramon, Dimona, Yeruham, Kiryat Shmona, Metula, Yesud Hama'ala and Tiberias. On Thursday messages will be sent to cell-phone owners in Jerusalem, Modi'in, Mevasseret Zion, Beit Shemesh, Ofakim, Lehavim, Arad, Ein Gedi, Afula, Hadera, Upper Nazareth and Zichron Yaakov.

This week's test is the final one before declaring the system operational in September.

At first, the cellular companies objected to cooperating with the Home Front Command, saying the warning system could cause panic. They demanded the Defense Ministry indemnify them in case of lawsuits. After further discussions the two sides agreed, based on legal opinions, that no compensation would be paid, just as none is paid in the case of false alarms.

Another issue raised in the discussions was whether the system could be defined as unsolicited, junk messaging. But since it is classified as a "life-saving" service, it was agreed that the Home Front Command could use it exclusively in emergency situations.

The Home Front Command is now drafting a suitable emergency announcement to be transmitted to cell phones - for example, warning their owners that they are entering a missile-landing area.

The IDF has been testing the system for several months, making especially sure it could not be hacked. "If someone hacked the system and could stop it from operating in an emergency or the reverse - operate it incessantly - it could be very dangerous. We must be immune to such hazards," a Home Front Command officer said recently.