An Israeli border guard on Sunday killed a Palestinian who tried to grab his gun when detained while trying to cross into east Jerusalem from the West Bank, a police official said.
The man was apprehended before he was shot while trying to grab a policeman's pistol in the confrontation before dawn, a police spokesman said.
However an Israeli human rights group said the man appeared to have been killed after he first tried to flee.
Karim Jubran of the Israeli human rights group B'Tselem said the Palestinian was among several undocumented laborers who had slipped across the barrier in hope of finding employment.
"After they crossed the fence, they came across a patrol car. They fled. The deceased was the last to flee. He was shot once by a border policeman," Jubran told Israel Radio, citing witness testimony gathered at the scene.
His neighbors later identified him as Ezzedine Kawasba, 38, a father of five from a small village outside the West Bank town of Hebron. They said he was a laborer who worked in Israel illegally.
Thousands of Palestinians sneak into Israel each day from the West Bank in search of work despite Israel's separation barrier, a network of walls and fences that snakes across the territory and through annexed east Jerusalem.
On September 22, clashes erupted in Jerusalem after a Jewish settlement guard shot dead a Palestinian during a confrontation in a tense neighborhood in the annexed Arab eastern part of the city.
Jerusalem is at the core of the Middle East conflict, with Palestinians seeing its eastern section as capital of a state they hope to found in the adjacent West Bank and the Gaza Strip.
Israel captured East Jerusalem from Jordan in the 1967 war and calls the whole city its "eternal, undivided"capital, a status not recognized abroad. After an armed Palestinian revolt erupted a decade ago, Israel erected a barrier that takes in much of East Jerusalem.