Yury Syomin, head of the City Prosecutor's Office, on Monday afternoon would not rule out a terrorist attack at the eastern Moscow market.

The dead included six Chinese nationals and one Vietnamese, Svetlana Petrenko, press officer for the City Prosecutor's Office, told Interfax. At least two of the people killed in the blast were children, Emergency Situations Ministry spokeswoman Yulia Stadnikova said. As of late Monday, six blast victims were in critical condition in the hospital.

Syomin announced Monday evening that two suspects had been arrested in connection with the blast but would not release names or any other information about them, citing the ongoing investigation.

Between 1 and 1.2 kilograms of TNT had been used in the blast.

The blast destroyed a 200-square-meter section of the market's Novaya Yevrazia wing, where hundreds of Asian food stores and cafes are crammed into narrow, covered alleyways and a fishy stench, compounded by the humid weather, fills the air.

The bustling market encompasses 20 hectares between the Lokomotiv soccer stadium and the Izmailovo Hotel. Everything from leather bags to crab meat to sneakers is sold in the vast maze of makeshift stalls.

Police and market security immediately cordoned off the blast site. Over the course of morning, police expanded their security zone, blocking reporters and the traders who work in the stalls there from gaining access.

Traders, who appeared to be mostly Chinese, Vietnamese and Central Asian, said they heard a huge explosion at around 10:30 a.m.

A Tajik trader, 38, surveying the throngs of onlookers from the second floor of the market, said he felt the shelves of the market shake. "I heard one explosion, at 10:27, and the stalls around me shook," said the man, who declined to give his name. "It happened about 500 meters away. I heard that one man of my nationality, from Tajikistan, was killed. He worked as a deliveryman."

One witness, also from Central Asia, said: "It was terrible. I saw puddles of blood. It was literally everywhere. One body was without a head."

Syomin added that it had been tough identifying the bodies. "According to their outward appearance, there may have been children, teenagers, or even what one may call small adults [among the victims], so it is difficult to tell," he said. "The bodies were badly damaged."

The blast is thought to have taken place at Atlantida, a Vietnamese cafe in the heart of the Novaya Yevrazia area of the market.

"It would appear that, initially, a explosive device was detonated, which led to the destruction of a gas canister," Syomin said. "The canister did not explode, but its lid was ripped off. That may have been the second bang that was heard."

Three or four suspects of Slavic appearance were seen entering the cafe, where they apparently deposited a bag and fled, Gazeta.ru and Channel One television reported, citing unidentified witnesses. As security guards began their pursuit of the suspects, the bomb exploded, the witnesses said.

Earlier Monday, there was widespread confusion about whether authorities had detained anyone in connection with the blast. Two suspects had been reported detained by authorities earlier in the day.

But Alexei Grigoryev, deputy head of the City Prosecutor's Office, disputed that report, saying only witnesses were being brought in for questioning. One minibus driven by a police officer was spotted hauling away five people thought to be witnesses.

Itar-Tass later reported that three people aged 18 to 25 had, in fact, been detained. The three were all thought to be members of the same gang, News.ru reported. The web site also reported that the Interior Ministry was drafting composite sketches of the suspects.

Families of those killed in the blast will receive 100,000 rubles, while those hospitalized with injuries will get 50,000 rubles, said Vladimir Platonov, City Duma chairman. Victims treated by paramedics on the scene will receive 5,000 rubles.

Nikolai Kulikov, head of the city department that works with law enforcement agencies, said there were simply too many people at the market to protect everyone. Kulikov added that the city would increase security in advance of City Day, on Sept. 2.

Markets across the country have been at the center of bloody feuds.

Most recently, a June 20 explosion in Samara killed the director of a market and his bodyguard. On May 26, a blast at Moscow's Petrovsko-Razumovsky market injured the director and his bodyguard. The explosion also destroyed the director's sports utility vehicle.

And in January 2005, a hand grenade injured six at a market in the Chechen capital, Grozny.

Markets in the southern city of Vladikavkaz have been targeted three times from 1999 to 2002, resulting in the combined deaths of 65 people.

Moscow's markets have also been hit by several gas explosions in recent years. On Feb. 4 of this year, a gas canister exploded at a market near the Bagrationovskaya metro station, injuring three people. In January 2002, one trader was killed in a gas explosion at a market near the Vykhino metro station.

In February, 66 people were killed when the roof of Moscow's Baumansky market collapsed under heavy snow.