UNITED NATIONS — An e-mail sent by a Canadian U.N. observer and obtained by FOX News casts doubt on claims by U.N. Secretary-General Kofi Annan that the Israeli attack on a U.N. peacekeeper observation post along the Lebanese border was intentional.

The email from Major Paeta Hess-von Kruedener warned that the post had come under "unintentional" artillery fire and aerial bombing several times in the previous weeks, and that several Hezbollah positions were in the area of the patrol base.

"It is not safe or prudent for us to conduct normal patrol activities," wrote Kruedener in the July 18th e-mail. "(The artillery and aerial bombing) has not been deliberate targeting, but has rather been due to tactical necessity."

Kruedener was one of four unarmed U.N. military observers killed in Tuesday's bombing.

"I think that e-mail is very important, because unfortunately these are practically the last words of somebody who eventually paid with his life," said Israel's U.N. ambassador Daniel Gillerman. "He's telling his commander that Israel was not targeting them and that there is Hezbollah activity around there."

This comes as the U.N. Security Council unanimously approved a statement on Thursday expressing shock and distress at Israel's bombing of the U.N. post, but fell short of condemnation