"The woman suicide bomber got out of the car and blew herself up," said the Israeli police commander in the West Bank, Shachar Ayalon. He said two other Palestinians who were in the car were badly injured in the blast. "They are on the ground and are in serious condition," he told Israel radio.
The bombing came after Israeli troops killed four armed Arabs in gun battles, and a Palestinian employee shot dead an Israeli factory manager in an attack that was apparently politically motivated.
The incidents followed a heated meeting between Palestinian and Israeli security commanders, convened to find ways to ease 17 months of conflict, as the top European diplomat, Javier Solana, traveled to Saudi Arabia to learn more about a Saudi initiative to settle the Mideast conflict.
The bombing attack was at a roadblock at the entrance to the West Bank from Israel on a highway between Jerusalem and Tel Aviv that passes near the West Bank town of Ramallah. There was no immediate claim of responsibility.
The blast shook windows in Israeli houses about two miles away across the border. Residents heard a loud explosion and then automatic gunfire.
A woman suicide bomber is a rarity, though more than 30 Palestinian men have carried out such attacks. On Jan. 27, a woman blew herself up in downtown Jerusalem, but it was unclear if she planned to commit suicide.
At the security meeting, with U.S. officials present, Israel demanded that the Palestinians dismantle militias associated with Palestinian leader Yasser Arafat's Fatah movement, said Israeli Defense Ministry spokesman Yarden Vatikay.
One participant, Jibril Rajoub, the Palestinian security chief in the West Bank, said the meeting was "very difficult." He blamed Israel for the recent escalation of violence and said he asked Israel to provide a timetable for lifting blockades that have kept most Palestinians in the West Bank confined to their communities.
Rajoub said there were heated exchanges between the two sides, but he said the forum would reconvene Thursday to discuss the situation in the Gaza Strip.
In violence Wednesday, Israeli soldiers killed three armed men who infiltrated from Egypt, the military said. One soldier was wounded in an exchange of fire with the infiltrators. Israel Radio said they were Palestinians, but military sources were not sure.
They crossed the Egypt-Israel border in a barren, unpopulated area 30 kilometers (18 miles) from the nearest Israeli town, Mitzpe Ramon. The military said the infiltrators had automatic rifles and a bag that may have contained a bomb.
The Egyptian government refused to comment, declaring a news blackout about the infiltration.
It was the first time the military reported tracking down armed infiltrators from Egypt into Israel since 1989, though Israel has complained of frequent smuggling of arms through tunnels under the border from Egypt into Gaza.
Early Wednesday morning, a Palestinian worker shot and killed his Israeli employer at a coffee factory in an industrial park north of Jerusalem. Israeli police said the shooting was apparently politically motivated.
The gunman, who had worked at the factory for three years, escaped into the area of the Palestinian town of Ramallah, where he lived, Israel Radio reported. The police clamped a news blackout on their investigation.
Before daybreak, Israeli soldiers shot and killed a Palestinian who was trying to plant a bomb next to an Israeli tank on the fringe of the Balata refugee camp, next to the city of Nablus, Palestinian witnesses said. The Israeli military had no comment.
Israeli tanks have held positions for several days on the Nablus street across from the camp, a known center for armed militias affiliated with Arafat's Fatah. The militias have claimed responsibility for many recent attacks against Israelis.
One of their leaders, Nasser Awais, 32, said he and his men would not halt attacks until the Palestinians won independence. "We are busy all the time finding (Israeli) targets, and we will strike where we can," Awais said in a telephone interview.
A 16-year-old girl wounded in a Palestinian suicide bomb attack at the West Bank settlement of Karnei Shomron on Feb. 16 died in a Jerusalem hospital on Wednesday, doctors said. Two other teen-agers were killed in the bombing along with the attacker.