Police officers gather near the entrance of the Electric Zoo music festival venue on New York's Randall's Island, Friday, Aug. 29, 2014. Heightened security has been placed at the festival, after the final day of last year's festival was called off. Two people died from an overdose of MDMA combined with hyperthermia at the festival last year. (AP Photo/Jason DeCrow)

NEW YORK, N.Y. - Drug-sniffing dogs, peers watching for people feeling ill, a "cooling tunnel" and shorter days are greeting fans this weekend at an electronic music festival where two people died of drug overdoses last year, organizers said Friday.

The three-day Electric Zoo began Friday on Randall's Island with beefed-up security and an emphasis on safety. Festival-goers had to watch a two-minute video about MDMA, also known as molly or ecstasy, to get a code to activate their access wristbands. Inside, the event featured free electrolytes and reusable water bottles along with the pulsating sounds and unusual sights for which it's known.

"You have everything short of a CAT scan here to make sure everybody is going to be safe," spokesman Stefan Friedman said.

The 5-year-old festival features such electronic-world names as artists David Guetta and Paul van Dyk, drawing thousands of people to a 27-acre venue. City officials cancelled its final day last year after two fans died from MDMA overdoses combined with hyperthermia; several others were hospitalized with what seemed to be drug-related problems, police said. A Buffalo, New York, man was arrested last month on federal charges of selling MDMA last year to three Electric Zoo patrons, including one who died.

Summer weather can make MDMA use especially dangerous, as the drug can make a user's body generate a lot of heat and cause the body's salt content to drop dangerously low, said Dr. Lewis Nelson, an emergency physician at NYU Langone Medical Center.

"Providing cooling stations and advice and observations for signs of hyperthermia are very important," he said.

That's the thinking behind the new cooling tunnel, a tent where fans can cool down, and the roughly 75 "ZooKeepers" — young adults, most with medical training, who will be paid to wander the crowd, look for anyone in distress and offer electrolytes and water.

A bigger security staff, including plainclothes police officers trained in drug investigations, also will be keeping watch.

Organizers don't think the new measures will deter patrons. Ticket sales are strong, Friedman said.

Still, to festival-goer Josue Franco, "it's an exaggerated response."

"I think it's a little unfair for everyone because not everyone uses drugs," he said. "But, still, l'm excited about it."

Others are fine with the added vigilance.

"We're all looking out for everybody," Frankie Massa said. "So the extra help, the extra security, the extra everything, it's good because it helps everybody be safe and not get hurt this year."

___

Associated Press writer Jennifer Peltz contributed to this report.

News from © The Associated Press, 2014