JERUSALEM, July 14 (JTA) — Israeli security officials have arrested three Palestinian police officers suspected of planning a terrorist attack near a Jewish settlement in the Nablus area. Acting on intelligence information, Israeli forces Monday arrested the three armed men. One of the Palestinian officers was lightly wounded by Israeli fire when he turned to shoot at the security officials. Investigators were verifying whether the police had any previous involvement in other terrorist activities. Israel Radio reported that two Palestinian policemen were suspected of involvement in last week’s roadside explosion on the outskirts of Nablus, in which two border policemen were wounded. In Bethlehem, meanwhile, a Palestinian youth was reported killed Monday when a bomb he was apparently preparing went off prematurely. Palestinian sources said the youth was a Hamas activist.