Five people have been killed in an Israeli air strike in the Gaza Strip, Palestinian officials say.
Pools of blood could be seen on the ground after the strike
An Israeli army spokeswoman said the strike had targeted a training area for militants in Gaza City.
The area is believed to be used by a group involved in launching rockets from Gaza into southern Israel.
Earlier in the day, Israeli troops shot and killed a Palestinian man during a stone-throwing demonstration in the city of Nablus.
The Israeli military said the militants were training for attacks on Israel.
"We carried out a strike against a terror target of the Popular Resistance Committees where armed militants were training," a spokeswoman told the AFP news agency.
Members of the group - one of the smaller militant organisations operating in Gaza - were on some kind of exercise in what is an area of trees and open ground, says the BBC's Alan Johnston in Gaza.
A official from the militant group, Abu Mujahid, told the Associated Press news agency that at least three missiles landed in the field. The strike left body parts scattered and pools of blood on the ground, the agency said.
The strike apparently took place close to the house of the group's top militant commander, Moumtaz Dourghmush.
He was not at the scene but some of his relatives were among the dead, hospital officials said.
Gunmen fired into the air and called for revenge outside the hospital where the dead men had been brought, Reuters news agency said.
In recent months, Israel has stepped up military activity in Gaza as a response to repeated rocket fire.
Last week, one Palestinian was killed and two injured in what the Islamic Jihad group said was an Israeli attempt to kill one of its leaders. Israel said it attacked militants on their way to strike Israeli territory.
Earlier, a man was killed in Nablus on a day when thousands of Palestinians took part in demonstrations in the West Bank and Gaza in support of the Hamas government.
The Israeli army said troops were carrying out a raid to arrest a militant when they encountered the demonstrators. The man who was shot was ready to throw a firebomb, the Israeli army said.