The Palestinian militant group Hamas says five of its members were killed in an Israeli air strike in southern Gaza Wednesday.

Hamas says the strike targeted a vehicle near the town of Khan Younis.

Israel's army confirmed the incident.

Separately, Palestinian militants and medical sources say an Islamic Jihad militant was killed Wednesday in a similar pre-dawn air strike in the central Gaza Strip. That incident was not immediately confirmed by Israel.

In other news, the United Nations' humanitarian chief told the U.N. Security Council on Tuesday that conditions in the Gaza Strip are "grim and miserable."

John Holmes, who recently visited Israel and the Palestinian territories, said the situation in Gaza has worsened since Israel imposed a blockade on the Hamas-ruled territory in mid-January.

Israel says it imposed the blockade to pressure Palestinian militants to stop firing rockets into Israel.

Holmes told the Security Council that the Palestinian rocket attacks must be stopped, but he said Israel's blockade is contrary to international humanitarian law.

Some information for this report was provided by AP and Reuters.