In a report published on Wednesday, the rights group said Israeli troops preferred to kill rather than arrest Palestinian suspects.
The report coincides with the publication by the London-based Amnesty International of its annual report in which it accused the Israeli occupation forces (IOF) of committing "war crimes" and "crimes against humanity" against Palestinians in the occupied territories.
Titled Taking No Prisoners, the B'tselem report contained affidavits and testimonies by a number of Palestinians stating that Israeli troops committed numerous acts of murder under the pretext of carrying "arrest operations".
"There is reasonable evidence that the Israeli Defence Forces, in some cases, behaved as if they were on assassination missions when in fact they were instructed to arrest suspects."
The report pointed out that the Israeli army killed 89 Palestinians during operations defined as "arrest missions", including 17 innocent people not "wanted" to the army.
The report also said that 43 of the 89 "wanted" Palestinians killed in 2004 were not indulging in any hostile actions against the army at the time of their death. The Israeli military police launched no investigations into these killings.
The B'tselem report, a copy of which was received by Aljazeera.net, cited two cases in which Israeli troops surrounded a house where a "wanted person" was staying.
However, instead of shooting the alleged wanted fighter, the soldiers shot another person as soon as he opened the door.
"There is reasonable evidence that the Israeli Defence Forces, in some cases, behaved as if they were on assassination missions when in fact they were instructed to arrests suspects"
Israeli human rights group
In two other cases, troops overpowered the "wanted person" and killed him on the spot, although he posed no threat to them.
The report said the army deliberately keep firing instructions vague so soldiers will not be prosecuted for "committing excesses".
But an Israeli army spokesman told Aljazeera.net that Israeli forces operating in the West Bank and Gaza Strip were taking "every conceivable effort" to avoid harming Palestinian civilians and innocent people.