JERUSALEM (AP) _ Carefully synchronizing their attacks, two men carried briefcases packed with explosives and nails into Jerusalem's most crowded outdoor market Wednesday and blew themselves up, sending body parts and blood-soaked vegetables flying.

The double blasts killed 15 people _ including the two bombers _ and injured more than 150, striking at the teetering Mideast peace process at a time when renewed progress seemed plausible.

Prime Minister Benjamin Netanyahu's Cabinet met in emergency session to suspend peace talks with the Palestinians _ which resumed this week after a four-month deadlock _ until Palestinian leader Yasser Arafat acts against the militants ``with determination,'' Israel TV said.

A leaflet claiming to be from the militant Islamic group Hamas took responsibility.

Mahane Yehuda, Jerusalem's main fruit and vegetable market, was packed with shoppers when the two bombs went off in an alley, about 50 yards apart, at 1:15 p.m.

``People flew in the air without legs, without arms, without clothes,'' said one witness, 43-year-old Sarah Yamin.

Soot-covered bodies lay on the ground, their blood mixing with smashed watermelons, torn clothes and shredded newspaper. Green awnings covering the alley were torn apart and vegetable stands and clothing displays overturned; scraps of clothing dangled from telephone lines.

The market has been the site of a dozen bombings and attempted bombings since the 1960s, but the latest assault was the deadliest.

The attackers _ whose overall aim has been to scuttle the peace process _ achieved a short-term goal: President Clinton postponed a new peace initiative by U.S. envoy Dennis Ross, who was to arrive in the region Thursday. No new date for the trip was set.

The attacks came just days after Netanyahu appeared on TV to highlight his success in preventing the deadly suicide bombings that bedeviled his predecessors and led to his election last year.

Shortly after the bombing, Arafat called Netanyahu to express his condolences, resulting in what Netanyahu spokesman Shai Bazak called a ``tough conversation.''

Later, at the emergency session of the Israeli Cabinet, Netanyahu said Palestinians' condolences were not enough: ``What we expect is action.''

One senior Israeli official, speaking on condition of anonymity, said Israel might resort to commando strikes or limited military offensives in Palestinian-controlled areas to try to stop the attacks.

Arafat, speaking in the West Bank city of Jericho shortly before declaring a state of emergency, said he ``strongly and completely'' condemns the violence, which he said ``is not only aimed at Israelis but at the peace.''

Arafat said he hoped Israel would not use the attacks as a pretext for further delays in peace talks, which collapsed in March over Israeli building into disputed territories and Israeli demands for a crackdown on Palestinian militants.

Israeli television reported that Arafat was expected to conduct mass arrests of Islamic militants in the West Bank and Gaza late Wednesday.

News reports said the two bombers apparently drove to the market together wearing black coats and white shirts _ perhaps in an effort to look like ultra-Orthodox Jews. Each carried a briefcase packed with 22 pounds of explosives, police said.

``I heard the explosions one after another,'' said 65-year-old Simha Kadoori, speaking from a hospital bed after doctors removed a 1-inch black nail lodged in her chest. ``I fell (and) saw blood on my chest.''

Dozens of ambulances lined up along Jaffa Road, one of Jerusalem's busiest streets, to carry away the dead and injured. A 14-year-old boy was seen with a badly mangled leg, and rescue workers tried to revive a boy about 8 years old.

Half a corpse, ripped apart by the force of the blast, lay covered with a blanket _ apparently one of the bombers.

Israeli TV said that beside the suicide bombers, eight men and four women were killed. Police identified two of the victims as David Nasco and Sammy Malka, both 44 years old and from the Jerusalem area. Authorities said early Thursday that one more civilian had died, bringing the toll to 15. The gender of that victim wasn't immediately known.

Shopkeepers were ordered to close their stores while police searched for more explosives. Bomb squads picked up blackened screws and nails, packed into the bombs to increase their deadly impact.

Dozens of Israelis gathered near the site of the attack, and some shouted, ``What kind of peace is this? Who needs this peace?''

A leaflet signed by Hamas claimed responsibility and demanded the release of the group's jailed spiritual leader, Sheik Ahmed Yassin, and all other Palestinian prisoners.

The leaflet said the demands must be met by 9 p.m. Aug. 3, but did not say what would happen if they were not.

Sheik Abdel Aziz Rantisi, the No. 2 man in Hamas' political leadership, cast doubt on the claim's authenticity, saying ``the tone of the leaflet is unusual.''

In Washington, Clinton urged the Palestinian Authority to take ``concrete steps'' to increase security in the region.

Israel immediately imposed a closure on the West Bank and Gaza Strip, barring tens of thousands of Palestinians from jobs in Israel.

Wednesday's bombings were the first since a March 21 attack on a Tel Aviv cafe in which three Israeli women and a suicide bomber were killed, and the most serious attacks in Israel since the February-March 1996 wave of bombings carried out by Hamas.