UN was providing intelligence to Hezballah

Strategy Page:

The UNIFIL Observer outpost that was "accidentally" targeted by Israeli firepower on July 25th, leaving four UN troops dead, was probably a victim of its own chatter. The unarmed observers, with a clear view of the fighting between Hizbollah and the Israelis, were apparently reporting whatever they saw, with other UNIFIL locations, over unencrypted ("in the clear") radio frequencies. This chatter could be picked up by Hizbollah. Since the Israelis have control of the air, and use aircraft and UAVs to gain an information advantage over Hizbollah, this UNIFIL chatter was giving the Hizbollah fighters information they would not otherwise have. That was endangering Israeli soldiers. Then again, the UNIFIL post was right in the middle of a battlefield. There was a furious firefight going on around the UNIFIL position, and the Hizbollah gunmen were using the UNIFIL position for cover from Israeli fire (an old Hizbollah tactic.) The Israeli damage to the UN bunker may well have been accidental.

Then again, Israeli troops have complained to UNIFIL about this sort of loose talk, and inadvertent shelter for enemy troops, before, but such complaints have been brushed aside. The Israelis have caught some UNIFIL actually working for Hizbollah, and many more of the UN troops developed very friendly relations with Hizbollah. There was always a practical reason for this. When UN troops give Hizbollah a hard time, Hizbollah is not bashful about threatening the UN troops with violence. But the UNIFIL/Hizbollah cooperation goes beyond idle chatter. At about the same time the UNIFIL troops were killed, other UNIFIL troops were repairing roads in the area that had been bombed by the Israelis. UNIFIL engineers were making the repairs so UNIFIL vehicles could use the roads again, but UNIFIL was not going to do anything to keep Hizbollah off the newly repaired roads.

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There is another possible reason for hitting the UN bunker. If Israel was using counter battery radar and Hezballah was firing from the area around the bunker, The Israelis could have given the coordinates provided by the counter battery radar to the pilots to suppress the rocket fire from the area without knowing about the UN position. They would merely be responding to enemy fire. I think this is probably the most reasonable explation for the bombing of that position. For some reason, Israel has not spoken about its counter battery radar, that I have seen, but I am confident that they have it and that they are using it on the border with Lebanon.