From BBC:

UN peacekeepers in south Lebanon contacted Israeli troops 10 times before an Israeli bomb killed four of them, an initial UN report says...

...The four unarmed UN observers from Austria, Canada, China and Finland, died after their UN post in the town of Khiam was hit by an Israeli air strike on Tuesday.

The UN report says each time the UN contacted Israeli forces, they were assured the firing would stop.

Israeli Prime Minister Ehud Olmert has expressed "deep regrets" over the deaths.

Israel is conducting an investigation into the deaths.

It has rejected accusations made by UN Secretary General Kofi Annan that the targeting of the UN position was "apparently deliberate".

White House spokesman Tony Snow said "something went really wrong" to cause the deaths, but also said there was no reason to suggest the bombing was deliberate.
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