Almost 2,000 box jellyfish unexpectedly invaded beaches along Waikiki and Ala Moana Beach Park yesterday, sending 177 people to seek treatment for stings.

Ocean Safety officials said the influx took them by surprise because they expected the peak to hit Friday, when 400 jellyfish were counted along south shores.

But as early as 10:30 a.m. yesterday, more than 40 people were standing in line at a Waikiki Beach lifeguard tower waiting to have stings tended to by city paramedics, according to emergency radio transmissions.

Bryan Cheplic, spokesman for the city Emergency Services Department, said five people were taken to hospitals for treatment but none of the situations were severe.

"It was mostly a precaution," he said.

Ashlei Limbaga, 20, of Wahiawa, and her cousin, 8-year-old Wailani Pascua, had barely gone in the water off Waikiki when Wailani started screaming, "It hurts! It hurts!" Limbaga said.

Lifeguards quickly responded with spray bottles of vinegar and cold packs to soothe the pain.

"They took such good care of her," said Limbaga, a student at the University of Hawai'i-Manoa. "The poor thing, the stings were on her lower stomach, up through her side and up on her arm. I'm glad she didn't go into shock because she's so young. You can see where the tentacles went across her body."

As of 7 p.m., she said her cousin's skin still showed the signs of the attack 7 1/2 hours earlier.

Limbaga said they didn't see warning signs about the jellyfish when they arrived at the beach, and the experience has made her more aware of the potential dangers.

"People need to know what can happen in the water. You really have to be educated about what's in the water and what to do about it," she said.

Officials had assumed that this month's influx of the tiny marine jellies, which can pack a very painful and occasionally deadly sting, would be relatively minor, since only about 400 of the creatures were found Friday, which was expected to be the peak arrival day.

"It just goes to show how unpredictable Mother Nature can be," Cheplic said.

Warning signs have been posted, but people headed for beaches staffed by city lifeguards should check with them before entering the water, he said.

"We'll be out on the beaches early Sunday to warn people and monitor the situation," Cheplic said. "We're hoping it will slow down."

Ocean safety experts say that the only way to prevent being stung is to stay out of the water.

For more information, visit www.808jellyfish.com or www.hawaiibeachsafety.org.