The gunfire, which erupted around 12:45 a.m., touched off a human stampede as tourists and gamblers tried to get out of the line of bullets. As they ran from the building, they jumped over slot machines and knocked over chairs.

"It was crazy, pandemonium," said Jade Jacobson, 28, a tourist from Deland, Fla., whose cousin, a dance teacher from Pennsylvania, was wounded in the leg. She added: "All I was thinking was that I could die right now."

Steven Zegrean, 51, of Las Vegas, was arrested and was expected to face felony charges including attempted murder, battery with a deadly weapon and discharging a firearm in an occupied structure, Las Vegas police Capt. James Dillon said.

He is expected to make an initial appearance in a Las Vegas court on Monday, a court official said. Zegrean did not yet have a lawyer late this afternoon, and was held without bail under suicide watch.

Authorities said Zegrean may have wandered the Las Vegas Strip for up to a day and a half before opening fire. Authorities described him as "greatly emotionally distressed" and said a relative reported he had tried to commit suicide on July 4. Police and paramedics responded to his home, but the report was ultimately determined to be unfounded, Dillon said.

Zegrean had extra ammunition in his tan three-quarter-length trench coat when he was apprehended, and may have wanted to provoke a fatal confrontation with police, Dillon said.

"This subject was capable and motivated to continue shooting," Dillon said, "but he was tackled and taken into custody after the first volley of rounds."

Melody Zegrean, 43, a Las Vegas resident who identified herself as Steven Zegrean's cousin, said he had been divorced for several years and estranged from most of his family since his ex-wife remarried.

"I love my cousin and everything," she said, "but his temper and not being able to relate has really gotten worse recently. He's been threatening the family for some time now. He's been pushing everyone away."

She described Steven Zegrean as a Hungarian immigrant and unemployed house painter who liked to gamble.

Police said they believed Zegrean entered the casino from a walkway connecting the New York-New York to the MGM Grand, and walked past a vendor and a shop before opening fire near the top of the bank of escalators.

Sixteen shots were fired before the gunman was subdued by two off-duty military reservists and two Florida Department of Law Enforcement special agents. Dillon identified the servicemen as Justin Lampert, a North Dakota Army National Guard member from Crosby, N.D., and David James, a Navy reservist from Jacksonville, Fla.

The Florida authorities, brothers Robert and Paul Ura, joined the reservists to disarm and subdue Zegrean, Dillon said.

"Absolutely, these men are heroes," Dillon said.

Lampert and James declined to speak with the media. A spokeswoman for the Florida agency said the Ura brothers would not be available for comment until they returned to their Tampa office on Monday.

All the injuries were described as minor, and none of the victims remained hospitalized. A woman and a teenage boy were wounded; a man was grazed by a bullet; a woman was hit by a bullet fragment or shrapnel; and a woman was bruised and scraped when she fell amid the crowd of people exiting the casino, Dillon said.

Troy Sanchez, a 13-year-old from Van Nuys, Calif., who was wounded in the left ankle, said he heard more than 10 gunshots from a balcony over an escalator that takes customers to the casino floor. He was with his mother and older brother, who works at the casino's Manhattan Express roller coaster.

"We thought it was fireworks," the teenager said. "I didn't even see the guy at all."

Sanchez and Jacobson's cousin, who declined to be identified, were treated at University Medical Center in Las Vegas and released. Dillon said both people with graze wounds and the woman who was bruised in the crowd were treated at the scene and released.

Larry Ramos, 33, a tourist from Lansing, Mich., said he arrived at the front of the hotel to find people rushing out.

"There were flip-flops just laying all over the place like people were running out of their shoes," Ramos said. "Within a minute and a half there were 30 to 40 police there. The cops just swarmed the place with M-16s and their guns out."

Ramos said bystanders cheered for the wounded when they were wheeled out of the casino to ambulances, and later talked about the people who tackled the gunman.

"People don't put up with stuff after 9-11 no more," he said, adding that he was surprised that the casino never shut down.

"That's what amazed me, Ramos said. "They locked down the tables, but they let people still keep playing the slots."

The 2,000-room hotel-casino, which opened in 1997, features a facade replicating the New York City skyline, with a 47-story knockoff of the Empire State Building, a 150-foot Statue of Liberty and a Coney Island-style roller coaster. It is owned by MGM Mirage Inc.