Israel's cabinet has authorised police to seal off "parts of Jerusalem", in an attempt to halt a wave of deadly attacks.
After an emergency meeting, the cabinet said soldiers would also be deployed to help police in some areas.
The moves come after police said three Israelis were killed and more than 20 hurt in shooting and stabbing attacks in Jerusalem and central Israel.
Two attackers in Jerusalem, identified as Palestinian, were shot by police.
Police said they acted after the assailants shot and stabbed passengers on a bus.
Another Israeli died after being run down and stabbed elsewhere in the city.
Later, a Palestinian was killed in clashes with Israeli forces in the West Bank city of Bethlehem, medics said.
Near-daily stabbings by Palestinians have left dozens of Israelis dead and wounded over the past fortnight. Several attackers and at least 18 other Palestinians have also been killed.
Tensions between Israelis and Palestinians have escalated since last month, fuelled by clashes at a flashpoint holy site in Jerusalem, in the West Bank, and across the Gaza border, as well as the wave of stabbings.
Israeli Prime Minister Benjamin Netanyahu's office announced the new measures after a crisis meeting of the country's top security officials.
"The security cabinet decided several measures to combat terrorism, notably authorising police to seal off or impose a curfew on parts of Jerusalem in case of friction or incitement to violence," AFP news agency quoted a statement by Mr Netanyahu's office as saying.
Many of the recent attackers were from Arab areas of occupied East Jerusalem, Israeli officials said.
The cabinet said soldiers would also be deployed to make public transport safe, and specially trained security guards would be recruited later.
It said the authorities could demolish the homes of Palestinians who attacked Israelis and take away their right to live in Jerusalem.
Mr Netanyahu said the new security measures would be aimed against "those who try murder and with all those who assist them".
He also told Palestinian Authority President Mahmoud Abbas to "stop lying, and stop inciting".
Mr Abbas has blamed "acts of aggression" by the Israeli authorities and Jewish settlers for the upsurge in violence.
In Tuesday's bus attack, the two assailants shot several passengers and stabbed others on board the vehicle in East Talpiot, a Jewish settlement in East Jerusalem also known as Armon Hanatziv, Israeli police said.
One of the assailants reportedly locked the bus doors in an attempt to stop police from boarding it and passengers from escaping, but police opened fire from outside and shot him.
Minutes later, a man ran over three people with his car at a bus station in the Geula district of West Jerusalem. He then got out of the car and attacked them with a meat cleaver. The attacker was shot by a security guard and seriously wounded.
Police spokesman Micky Rosenfeld identified all three attackers as residents of the Jabal Mukaber district of East Jerusalem.
Earlier on Tuesday, a Palestinian stabbed an Israeli man, moderately wounding him, at a bus stop in Raanana, a town north of Tel Aviv, police said. The attacker was captured and reportedly beaten and seriously injured by passers-by.
Not long afterwards, at least four other people were wounded in another knife attack in Raanana, police said. The assailant fled, but was then arrested by police.
Police identified both of the attackers in Raanana as residents of East Jerusalem.
On Tuesday afternoon, clashes between Palestinian protesters and Israeli forces continued in the West Bank after activists called for a "day of rage"
Palestinian medics told the AFP news agency that at least one Palestinian was killed and 15 others wounded by Israeli fire.
In the US, Secretary of State John Kerry said: "The United States condemns in the strongest terms possible the terrorist attacks against Israeli civilians. No matter who it is, this violence, and any incitement to violence has got to stop."
What is happening between Israelis and Palestinians?
There has been a spate of stabbings of Israelis by Palestinians since early October, and one apparent revenge stabbing by an Israeli. The attacks, in which some Israelis have died, have struck in Jerusalem and elsewhere, and in the occupied West Bank. Israel has tightened security and clashed with rioting Palestinians, leading to deaths on the Palestinian side. The violence has also spread to the border with Gaza.
What's behind the latest unrest?
After a period of relative quiet, violence between the two communities has spiralled since clashes erupted at a flashpoint Jerusalem holy site in mid-September. It was fuelled by rumours among Palestinians that Israel was attempting to alter a long-standing religious arrangement governing the site. Israel repeatedly dismissed the rumours as incitement. Soon afterwards, two Israelis were shot dead by Palestinians in the West Bank and the stabbing attacks began. Both Israel and the Palestinian authorities have accused one another of doing nothing to protect each other's communities.
Is this a new Palestinian intifada, or uprising?
There have been two organised uprisings by Palestinians against Israeli occupation, in the 1980s and early 2000s. With peace talks moribund, some observers have questioned whether we are now seeing a third. The stabbing attacks seem to be opportunistic and although they have been praised by militant groups, Palestinian leader Mahmoud Abbas has said Palestinians are not interested in a further escalation.