An 8-year-old girl drowned and her father, brother and another child died trying to rescue her from a deep, swirling pool at a water garden where "No swimming" signs are posted.

About 2,000 people gathered for a prayer vigil Thursday morning, a day after the deaths of the four, who were visiting from Chicago to attend a Sunday school convention.

"Today our city extends our wings to enfold and comfort you," Mayor Mike Moncrief (search) told the crowd, many of whom held hands and wiped away tears.

The four had gone to the 5-acre Fort Worth Water Gardens (search) because the pool at their nearby hotel was closed, said the Rev. Gerald M. Dew, pastor of Antioch Missionary Baptist Church in Chicago.

The water gardens, which are not meant for swimming, feature fountains and waterfalls fed by pools that use powerful motors to circulate the water. Residents said people often wade in the pools on hot days.

The victims were identified as Myron Dukes, 35; his daughter Lauren, 8; his son Christopher, 13; and Juantrice Deadmon, 11, who was not related to the other three.

Witness accounts of the accident varied. Apparently, Lauren jumped or slipped into the water. Juantrice tried to reach in and help her but fell in herself. Lauren's father and brother then jumped in to try to save the girls.

Police officer Tony Moldanado, one of the first rescuers at the scene, told the Fort Worth Star-Telegram that when he jumped in, the suction "literally sucked the socks off my feet."

One witness, Christian Tillis, 14, said he saw the girls slip into the water and tried to help.

"I dived in after them. I felt a little-bitty hand, but it slipped out," he said. "And then I had to get out because I couldn't breathe."

The 9-foot-deep pool, called the Active Pool, collects water from several waterfalls. At the bottom, a powerful pump pulls the water through a drain so it can be recirculated, fire officials said.

At Thursday's service, Dew urged mourners to remain faithful.

"In spite of the tragic events of yesterday, God is still on the throne," he said.

Before Wednesday, the park's most serious accident was in 1991, when an 80-foot light pole fell and killed two people. The city has paid thousands of dollars in claims to visitors injured in falls, the Star-Telegram reported.

Designed by architects Philip Johnson and John Burgee, the gardens are free to enter and a common refuge from hot Texas days. Each minute, 19,000 gallons of water courses through the garden, according to the Fort Worth Convention and Visitors Center (search).

"No swimming" signs are posted in the park, city spokeswoman Dot Kent said.

But Jesse Spann, one of the church's deacons, said there are no barriers around the area and that there are steps leading down to the swirling pool. "As a child, when you see a waterfall, you think you can go play and swim there," he said.

Fire Department spokesman Lt. Kent Worley said the Water Gardens would remain closed until police finish their investigation.