The Palestinian government has asked the United Nations to launch an investigation into alleged extrajudicial killings by Israel.

Monday's request follows the deadly shooting last week by an Israeli soldier of a wounded Palestinian assailant as he lay on the ground. The military has detained the soldier while it investigates.

Palestinian official Saeb Erekat said that past Israeli investigations have failed to "serve justice" and instead, he claims Israel has been "rewarded with impunity."

The shooting came amid a six-month wave of Palestinian attacks that have killed 28 Israelis and two Americans.

Over the same time, at least 188 Palestinians have died by Israeli fire. Israel says most of those were attackers while the rest died in clashes with Israeli forces.

The Palestinians say the killings amount to extrajudicial slayings.