Israeli troops have killed an armed Palestinian in the southern Gaza Strip, near the border fence east of Rafah.
All attention has been on Gaza now open border with Egypt
The militant group al-Aqsa Martyrs Brigades, an offshoot of Palestinian leader Mahmoud Abbas's Fatah party, said one of its members had died.
The killing refocuses attention on the Israeli border 10 days after Gaza's Egypt border was breached by militants.
Cairo has hosted talks with Mr Abbas and Gaza's de facto rulers, Hamas, but failed to get them to work together.
Clashes have been common between the Israeli army and Palestinian militants and rocket launchers near the Israel-Gaza border, with dozens of militants, and some civilians, killed in recent months.
Al-Aqsa Martyrs members said the Israeli army prevented Palestinian ambulances from reaching the scene of the incident.
Mr Abbas left Cairo for the West Bank shortly after meeting President Hosni Mubarak on Wednesday, saying there would be no talks with Hamas unless they reversed their "coup" in Gaza.
Egypt had also invited a delegation of senior Hamas officials, including Damascus-based leader Khaled Meshal, to Cairo.
17 January: Israel seals border following rise in rocket attacks
20 January: Gaza's only power plant shuts down
22 January: Israel eases restrictions
23 January: Border wall breached
27 January: Hamas asked to talks in Cairo, after it fails to reseal border
Mr Meshal arrived in Cairo for a rare visit just after midnight. Reports say he is expected to hold talks with Mr Mubarak on Thursday.
Tens of thousands of Palestinians have crossed the border into Egypt at Rafah, to stock up on food, fuel and other supplies since the border was open last Tuesday.
Wary of popular feelings at home, Egypt troops have avoided any harsh crackdowns on the border, despite strong pressure from Israel which is worried about arms smuggling.
Until last week's unprecedented break-out, Cairo had firmly backed Mr Abbas and shunned Hamas, but correspondents say the new situation in Gaza has forced Egypt to rethink its position and engage with Hamas.
The Gaza Strip has been under an almost total blockade since Hamas ousted Fatah forces in Gaza last June.
On Wednesday, Israel's supreme court upheld the cabinet's decision to reduce fuel and electricity supplies to Gaza in response to continued Palestinian militant rocket fire into Israel.
The Israeli measure, which it later partially eased, was followed by the breaching of the Gaza-Egyptian border.