Palestinian security and medical sources said explosion occurred at a house belonging to Ahmed Hamudi, a senior Hamas commander, CNN reported. Witnesses called the blast a "work accident."
Israeli denied involvement in the incident, calling it a Palestinian internal matter..
Israeli troops killed three Palestinian gunmen in Gaza Thursday, including two members of the military wing of Fatah, Ynetnews.com reported. Israeli army officials said troops stopped an attempt by the Al-Aqsa Martyrs' Brigades to plant explosives near the Gaza border.
An investigation said military spotters identified two gunmen approaching the border fence opposite an Israeli town, apparently intending to plant a bomb on the fence, officials said. The two sides began exchanging gunfire.
Senior Israeli Defense Ministry official Amos Gilad traveled Thursday to Cairo to try to secure an Egyptian-mediated cease-fire with Hamas and the other groups in Gaza. Gilad was expected to brief Egyptian Intelligence Minister Omar Suleiman on Israel's conditions.
Besides a comprehensive cease-fire in Gaza, Ynetnews.com said conditions include the release of kidnapped Israeli soldier Gilad Shalit and an end to arms smuggling to Gaza from Egypt.