While the headlines are focusing on the Katsav trial, the protests in Syria and the implications of the earthquake in Japan, a small war has been going on for a week now along the Gaza border.

Israeli communities near the border are receiving a daily dose of mortars and rockets, and the Israel Air Force has been attacking Gaza. What began as a local escalation is steadily transforming into a broader conflict that the sides will apparently have difficulty stopping, though it's doubtful either side has an interest in reaching that point.

The current tensions began exactly a week ago when Israel launched an air attack on a Hamas base in the ruins of the settlement of Netzarim, killing two Hamas men. That attack came in response to a Qassam fired from Gaza that landed in an open area. Hamas then responded with a barrage of 50 mortars on communities south of the Gaza Strip. Israel delayed its response so as not to disrupt the Purim festivities in the Sderot area.

But on Monday evening Israel launched a series of air attacks in which a number of Hamas militants were wounded. Things worsened yesterday afternoon. After a round of mortar fire on kibbutzim east of Gaza, the Israel Defense Forces fired its own mortars right back at the source of the firing - at the Sajaiyeh neighborhood east of Gaza City, killing four members of a family, including two children.

Southern Command's initial investigation indicates that the mortars' launching point, an olive grove on the edge of a residential quarter, had been clearly identified. It seems that a number of the IDF's mortars went off course and hit a house in Sajaiyeh, a few dozen meters from the grove.

The IDF says armed Hamas men who had fired mortars at Israel were also hit in the strike, and has expressed regret about innocent casualties. The IDF says it fired to stop the firing in the Sha'ar Hanegev Regional Council. The commander of the sector used mortars of a type known as keshet for lack of more precise weapons, which were not available quickly enough due to the urgency of stopping the Palestinian mortar fire at the kibbutzim.

Military officials said yesterday that Israel has no interest in an escalation, which echoed precisely Hamas' statements from the day before. Until the Sajaiyeh incident, it seemed that Hamas was again trying to enforce calm.

Now the picture is once again more complicated. Hamas TV repeatedly showed close-ups last night of the body of an 11-year-old boy, Mohammed Jihad al-Halu, who was killed by IDF fire. Hamas' military wing released a relatively cautious statement, but the other factions have vowed revenge.

The more time that passes and the larger the number of casualties, the harder it will be to stop the escalation.