Two women wearing explosives blew themselves up outside the Krylya rock festival Saturday, killing at least 13 and injuring more than 50 in the first suicide bombings to rock Moscow.

The authorities immediately blamed the attack on Chechen rebels, and President Vladimir Putin canceled a trip to Uzbekistan and Malaysia that was to begin Sunday.

The first woman detonated a belt of explosives packed with scraps of metal at 2:45 p.m. at the main entrance to the fenced-in Tushino airfield, where a crowd of some 40,000 were watching bands perform at the annual festival.

The woman, who bought a ticket at a nearby clothes market, was agitatedly pushing her way through the line when police officers screening concert goers with a portable metal detector spotted her and tried to lead her away, the Interior Ministry and eyewitnesses said.

"She was excited and pushed her way through the line to the entrance. When the police approached her to lead her away, she knew she had been caught and detonated her bomb," said an eyewitness, a young man who asked not to be identified.

However, only a third of the explosives detonated, injuring three people. The explosion ripped open the woman's stomach, and she died shortly afterward.

Fifteen minutes after the blast, a woman detonated a similar belt near the concert's main ticket offices about 100 meters away. The force of the blast tore the woman apart and killed 11 passers-by. More than 50 people were injured.

Two more people died later in the hospital, bringing the death toll Sunday to 13 plus the two suicide bombers.

No arrests had been made as of Sunday, and no one had claimed responsibility. But officials said a passport found in the debris showed that one of the bombers was Zalikhan Elikhadzhiyeva, a 20-year-old resident of the Chechen village of Kurchaloi.

Thirty-eight people remained hospitalized Sunday, including five in critical condition, Interfax reported, citing health officials.

The injured were taken to the Botkin hospital, the Sklifosovsky emergency hospital, the Pervaya Gradskaya Hospital and city hospitals Nos. 67, 33 and 37, police spokesman Valery Gribakin said.

Police were still trying to identify bodies Sunday afternoon, he said. "Some don't have faces. Others are missing other body parts," he said.

Gribakin read off a list of names of 14 people whose documents -- student ID cards, train tickets and passports -- had been found at the second blast site. Most of those killed were born in the early 1980s. One of the victims was a young child.

Chechen rebel leader Aslan Maskhadov, speaking through his Moscow-based representative Salambek Maigov, denied any involvement in the attack.

First Deputy Interior Minister Rashid Nurgaliyev, however, said on Rossia television Sunday that relatives of the Chechen woman whose passport was found have connections to rebels.

Interior Minister Boris Gryzlov said the attack could be tied to a decree signed by Putin last Friday night ordering the Chechen presidential election to be held Oct. 5. The rebels oppose the vote, which is to be followed by regional parliamentary elections in a Kremlin-drafted peace plan.

Khusein Isayev, head of the Chechen State Council, said he doubted that there was a link but predicted more attacks to destabilize the situation in Chechnya ahead of the vote, Interfax reported.

Putin on Sunday was to fly to Uzbekistan and then Malaysia, where he was to sign a $900 million deal on supplying Su-30MK fighter jets. But the Kremlin said in a statement Sunday that he had decided to call off the trip "in connection with the tragic consequences of the terrorist act in Moscow." The Kremlin did not elaborate.

"The goal of this terrorist act is obvious -- to seed fear, suspicion and ethnic intolerance in our society," Putin said in a statement released Sunday on Rossia. "We know that betrayers of their own people and murderers don't have and can't have a future."

Initial news reports said the organizers of the attack might have fled in a white Gazel van with a Stavropol license plate, but the police later denied that.

Gryzlov ordered security boosted at hospitals, theaters and shopping centers, and that guards armed with metal detectors and sniffer dogs be present at all mass gatherings, including concerts. He praised the police for preventing the bombers from getting into the festival.

Moscow Mayor Yury Luzhkov, together with Gryzlov and Emergency Situations Minister Sergei Shoigu, visited the scene of the attack Saturday. City authorities decided not to stop the show, fearing the spectators -- many of them intoxicated teens -- might panic. They later provided 200 buses to ferry those leaving the concert to the Sokol metro.

Many in the crowd did not hear the explosions over the loud music and only found out when anxious relatives and friends started calling their cellphones.

But shortly after the blasts, the authorities blocked all cellphone calls to the area to allow the audience to enjoy the rest of the concert oblivious of the carnage, the BBC reported.

"I thought it was fireworks or maybe that they had started spraying water out of a truck," said Yevgenia Savina, 18, who was standing near the stage, about 200 meters away from the blasts.

"Rumors started spreading really quickly," said Andrei Mikhailov, 22. "People started saying that someone was sneaking in cellphones filled with explosives."

Anxious parents -- some not bothering to change out of their bathrobes after hearing the news on television -- rushed to the airfield, but the police barred them from entering. Many spent hours clinging to the bars of the fence around the field, hoping to catch a glimpse of their children.

"If only I knew that she was all right," said Valentina Smirnova, who came to the airfield after failing to reach her 18-year-old daughter Sonya on her cellphone. "She just passed her exams at the institute. She and her friend Olesya wanted so much to go to celebrate the start of their vacation."

Many fans and the concert organizers seemed less concerned, and the music went on for six hours after the attack.

Rock musician and concert organizer Sergei "Serga" Galanin told a hastily called news conference Saturday afternoon that he did not feel it was disrespectful to those killed to continue the festival. "We're not playing fun songs, nobody's having fun out there. They're playing rock music and talking about serious things," he said, even as the sound of a wild guitar solo and a screaming crowd wafted across the field.

Luzhkov insisted the attack would not disrupt life in the capital and said there was no reason to call off the city's annual outdoor beer festival, which opened Saturday. But attendance at the festival fell significantly Sunday.

Saturday was the first time that suicide bombers -- who have staged several attacks in Chechnya in the past year, killing scores -- have managed to successfully carry out an attack in Moscow.

Moscow saw its first suicide bombers in October, when a group Chechens, including women wearing belts with explosives, took 800 people hostage at the Dubrovka theater. Special forces used gas to knock out the rebels before they were able to detonate their explosives.

(The Moscow Times 07.vii.03)