Palestinians took to the streets for noisy rallies and a mass funeral to bury those killed in confrontations with Israeli troops.
Israeli troops fatally shot six Palestinians in two separate confrontations on Sunday evening along the northern edge of the Gaza Strip.
Israel say all six were preparing to carry out attacks, though it gave contradictory information on one of the shootings.
"During these difficult times we are living in, our people are still fighting against all the Israeli challenges," Palestinian leader Yasser Arafat told a cheering crowd of 6,000 in the West Bank town of Ramallah.
"We are the strong people. The Palestinian flag will be flown above the walls of Jerusalem," he added.
Three of the dead Palestinians were trying to cross the fence on Gaza's northern border with Israel. Israeli forces spotted the trio and ordered them to halt. One Palestinian opened fire, and all three were killed by Israeli return fire, the army says.
"Judging by the belt bombs, the weapons and the grenades, they intended to carry out a major attack," Israeli Brigadier General Israel Ziv, the commander of the Gaza Strip, told army radio.
The dead included Ismail Abu al-Qumsan, a prominent activist and a leader of the Popular Resistance Committee, which is made up of various Palestinian organisations, including Arafat's Fatah movement.
In the other shooting, which took place only a short distance away, three Palestinians were shot as they approached the Alei Sinai settlement at the northern end of Gaza Strip. The army initially said the Palestinians opened fire and were believed to be in the process of planting a bomb.
But the army now says the trio had no firearms, just one commando knife and one kitchen knife. The army says it is still investigating to determine whether the three were carrying explosives.