"Egyptian officials say Israeli forces chased the suspected militants across the border, and a number of people were killed – including the [five] police officers." - Guardian// If the IDF actually crossed the border, an apology is certainly due and perhaps even an offer to compensate the families. If there was only a cross-border fire exchange, then an expression of regret is sufficient in principle. In any case, Israel should keep Lieberman out of the discussions in this case. He will only cause more trouble.
Report: U.S.-led strikes in Iraq, Syria killed 459 civilians (AP)
from the article: Israel and Egypt to hold joint probe into deaths of Egyptian policemen