Members of the Palestinian security services confirmed that three Islamic Jihad members had been killed after clashing with Israeli troops but gave no further details.
Islamic Jihad, one of the smallest of the various Palestinian armed groups, has not publicly commented on the reports.
Hamas minister detained
Separately, police in Belgium briefly detained a Hamas minister of the Palestinian unity government as he travelled from Egypt to the Netherlands.
Police in Brussels airport prevented Basim Naim, the minister of Youth and Sports, from leaving an Egypt Air flight which had travelled from Cairo to the Belgian capital on Friday afternoon.
"They [police] told us not to leave the plane and are not even allowing us to get up from our seats. They have acted in a provocative manner," he told al-Jazeera by telephone.
Naim has been planned to travel from Brussels to Rotterdam, the Netherlands' second city, in order to take part in the fifth European Palestinians conference which will take place on Sunday.