An explosion in the northern Gaza town of Beit Lahiya has killed a Hamas activist and injured three others.
Media reports say the blast occurred while the militants were carrying an explosive device.
In other news, Israel says Palestinians in the Gaza Strip fired a mortar shell at the main crossing for cargo between Gaza and the Jewish state early Tuesday.
Israel's army says the shell hit a truck that was delivering building materials to Gaza through the Karni crossing. The truck driver was hospitalized.
It was the latest breach of a November ceasefire between Israel and Gaza militants.
Meanwhile, Palestinian police are still searching for a Peruvian news photographer kidnapped Monday by gunmen in the Gaza Strip. Jaime Razuri of Agence France Presse was abducted outside the agency's Gaza bureau.
AFP reported that a delegation from the agency met Tuesday with Palestinian security chiefs, but there has been no news on the identity of the abductors or their motives.
Kidnappings have become frequent in Gaza, which is increasingly lawless.
The photographer was abducted as new clashes broke out between Palestinian factions in the Gaza Strip. Fatah and the governing Hamas group agreed to a ceasefire in December, ending weeks of deadly violence.