Palestinian medical officials say Israeli troops have killed four Palestinian militants in the West Bank town of Bethlehem.
Security sources say those killed included a member of Islamic Jihad and a member of the al-Aqsa Martyrs Brigades.
The incident came after the leader of the Islamic militant group Hamas laid out conditions Wednesday for a cease-fire with Israel.
Ismail Haniyeh said Israel must stop carrying out raids and assassinations in the Gaza Strip, and must re-open the territory's borders. He also said a cease-fire must be "reciprocal, simultaneous and comprehensive."
Israeli Defense Minister Ehud Barak said today Israel has not entered into a truce with Hamas. He said there has been no change in Israeli efforts to stop Gaza militants from firing rockets into Israel, saying there could be an escalation of fighting.
Also Wednesday, a security official says a Palestinian smuggler died when the tunnel he was digging between the Gaza Strip and Egypt collapsed on him.
The officials says five of the smuggler's companions escaped back into Gaza.
A lull in violence in recent days has followed an Israeli military offensive in Gaza in which at least 120 Palestinians were killed. Israel launched the offensive in response to Palestinian rocket attacks on southern Israel that killed one civilian.
Hamas' charter calls for the destruction of Israel. Israel, the United States and the European Union consider Hamas a terrorist group.
Gaza's borders have been sealed since Hamas seized control of the territory in June.
The al-Aqsa Martyrs Brigades is the armed wing of the Fatah movement of Palestinian President Mahmoud Abbas.
Earlier today, Israeli troops killed an Islamic Jihad militant around the West Bank town of Tulkarm.
Some information for this report was provided by AFP and AP.