Israeli-Palestinian violence spreads over Gaza border
Fresh violence between Palestinians and Israelis has seen six Palestinians shot dead in Gaza, reports say, and a fresh spate of stabbings.
Israel said its troops fired over the Gaza border after coming under attack.
Earlier, police said there had been the first apparent revenge stabbing attack by an Israeli on Arabs.
Tensions between Israel and the Palestinians have recently soared amid a rash of attacks and confrontations between Palestinians and troops.
Since last weekend, gun and knife attacks by Palestinians have left four Israelis dead and many wounded, while at least three Palestinians have been killed during clashes with security forces in the West Bank and East Jerusalem.
According to Palestinian medical sources, the six Palestinians were shot dead and many others wounded in two separate incidents in Gaza on Friday when Israeli troops opened fire.
The Palestinians were protesting in solidarity with Palestinians in Jerusalem and the West Bank.
The Israeli military said more than 1,000 rioters had massed at the border fence, throwing a grenade and rocks, and rolling burning tyres at Israeli forces.
After firing warning shots, troops fired towards the "main instigators" to disperse the riot, a military statement said.
Analysis: Yolande Knell, BBC News, Jerusalem
With tensions running high after a week of stabbings and violent clashes, much hinges on what happens in the coming hours.
Extra Israeli security forces have been deployed in Arab neighbourhoods of East Jerusalem. There are new metal detectors in the Old City and roadblocks nearby.
It is proving a struggle to prevent the sporadic lone wolf attacks by young Palestinians. These have been motivated by deep anger over access to al-Aqsa Mosque and the current political situation. There is a danger that a heavy-handed Israeli police response could exacerbate the situation.
Israeli officials blame the Palestinian leadership for exploiting the sensitivities around al-Aqsa - which is on a site sacred to both Muslims and Jews - to incite violence. Palestinian authorities say Israeli policies are to blame.
So far the scale of violence does not amount to a third Palestinian intifada, or uprising. Yet the danger remains that this could escalate and spin out of control.
Violence also continued in Israel on Friday, including what police said was an apparently "nationalistic" attack by an Israeli, who they say stabbed two Israeli Bedouins and two Palestinians.
The attack, apparently in retaliation for stabbing attacks on Israeli Jews this week, occurred in the southern city of Dimona.
The suspect was arrested and is being questioned.
Israeli Prime Minister Benjamin Netanyahu said he "strongly condemned the harming of innocent Arabs" and vowed to bring to justice anyone who breaks the law.
The mayor of Dimona said the suspect was "a mentally ill man", the Associated Press news agency reported.
Shortly afterwards, an attacker was shot dead after stabbing an Israeli policeman near Hebron.
In Jerusalem, a 16-year-old ultra-Orthodox Jewish Israeli was stabbed and wounded. A Palestinian suspect fled but was caught by police.
An Israeli policeman, meanwhile, was injured and his assailant shot dead near the Jewish settlement of Kiryat Arba, close to Hebron. Separately, a Palestinian woman was shot and wounded after trying to stab a guard at a bus station in Afula, northern Israel, police said
Friday's attacks follow a sharp rise in violence between Israelis and Palestinians since late last month, when clashes erupted at a flashpoint holy compound in East Jerusalem.
An Israeli couple were shot dead in the West Bank in front of their four children, while two more Israelis were killed in a stabbing in Jerusalem's Old City days later - the first in a spate of stabbings of Israelis in the city, northern and western Israel and the West Bank.
Hundreds of Palestinians have been wounded and at least three, including a 13-year-old boy, shot dead in clashes in the West Bank and East Jerusalem during the same period.
Five of the Palestinians who apparently carried out the stabbings have been killed.
Israel has boosted security across the country and imposed temporary restrictions on Palestinians wanting to enter the Old City of Jerusalem.