Five Palestinian militants have been killed in three separate Israeli air strikes in the Gaza Strip.

Israeli officials say they targeted militants trying to enter Israel, near a crossing point in Gaza, and other Hamas militants who were traveling in a car laden with explosives. Noa Meir - a spokeswoman for the Israeli Defense Forces - says no particular Palestinian group was targeted.

"It is not a matter of targeting Hamas, per se, but of targeting these terrorists and Hamas are these terrorists. The first attack was against a Hamas terrorist cell on its way to carry out attacks against Israel," she said. "There were secondary explosives from their car, indicating they were on their way to commit this attack. The second was against terrorists who were involved in planning terrorist attacks in the past and in the future."

Tuesday, Israeli border police arrested the head of Force 17, Palestinian President Mahmoud Abbas' personal protection service, saying he had been wanted for six years for carrying out terrorist attacks.

Israeli military forces re-entered the Gaza Strip in late June, after Palestinian militants abducted an Israeli soldier in a raid on a Gaza border outpost.

Wednesday, Israeli newspapers report defense officials are concerned that Palestinian militants are trying to obtain advanced Russian-made anti-tank missiles. The missiles were used by Hezbollah militants in Lebanon during the recent conflict there with deadly effectiveness. Israeli military authorities say the bulk of their casualties in Lebanon were caused by the missiles, which can penetrate heavy armor and reinforced concrete structures.