GAZA CITY (CNN) -- Israeli airstrikes and ground battles with Palestinian militants on Wednesday left 21 dead, most of them Palestinians, according to Palestinian security sources.
Palestinians say a Reuters cameraman and two others died Wednesday when a missile hit this vehicle.
A Reuters cameraman and two bystanders were killed in an apparent airstrike near El Bureij refugee camp in central Gaza, according to Hamas security sources and Palestinian medical sources.
Ten other Palestinians -- five militants and five civilians -- were also killed near El Bureij in an Israeli airstrike, Hamas security sources said. It is unclear if it was the same incident that killed the journalist.
The sources identified the five slain militants as members of a new radical Islamic group called El Oma Army.
The Israeli military confirmed an airstrike that targeted militants in El Bureij but had no information on casualties.
Later, in a statement, the Israeli military said: "We wish to express sorrow for the death of the Palestinian cameraman. On that note, it should be emphasized that the area in which the cameraman was hurt is an area in which ongoing fighting against armed extreme and dangerous terrorist organizations occurs on a daily basis."
The statement added, "The presence of media photographers and other uninvolved individuals in areas of warfare is extremely dangerous and poses a threat to their lives."
Reuters identified the cameraman as Fadel Shana, 23, and said he was getting out of the vehicle when an explosion killed him and two bystanders. Witnesses said it was caused by an Israeli airstrike.
The cameraman's colleagues identified his body at a hospital, according to Reuters' Web site.
Earlier in the day, three Israeli soldiers were killed when troops exchanged gunfire with Palestinian gunmen who were making their way toward the border between Gaza and Israel, just south of the Nahal Oz crossing, an army spokesman said. The gun battle wounded a few other soldiers.
Four Hamas members were killed when soldiers entered northern Gaza in a routine operation against militants, an Israeli military spokeswoman said. Palestinian security sources confirmed the deaths.
Hamas security sources said an earlier airstrike killed a Palestinian farmer in northern Gaza near Beit Lahiya. The Israeli military said its aircraft fired at armed men entering a car, hitting one of them.
Meanwhile, Israel resumed some fuel shipments to Gaza on Wednesday, a week after Palestinian militants shot and killed two Israeli civilian workers at the Nahal Oz fuel terminal -- the only transit route for delivering fuel supplies to Gaza.
Israel began shipping diesel fuel to Gaza's power station at 2:30 p.m. (7:30 a.m. ET), according to a spokesman for Israel's coordinator of activities in Gaza.
Israel halted fuel supplies from Nahal Oz to Gaza after last Wednesday's attack.
CNN's Michal Zippori and Ben Wedeman in Jerusalem contributed to this report.