MIAMI – Two Icelandic skydivers who died during weekend jumps at a popular southwest Florida camp did not deploy their main parachutes, the co-owner of the facility said Sunday.

Deputies found the bodies of the skydiving instructor and a student Saturday after the two didn't return from a jump with a group, setting off an hourslong air and ground search around the Zephyrhills facility, about 30 miles northeast of Tampa. Pasco County sheriff's authorities identified the victims as 41-year-old instructor Orvar Arnarson and 25-year-old student Andrimar Pordarson of Iceland. The men jumped separately, not in tandem.

The fact that the men didn't deploy their main parachutes could mean that they lost altitude awareness and didn't know where they were during the dive, which is unusual, said T.K. Hayes, co-owner of Skydive City.

Both men had backup automatic activation devices, which deploy if the main parachutes are not deployed in time.

"Those devices activated on both of them ... but the reserves did not have time to deploy fully," Hayes said. "They were out of the containers but not inflated in time before they impacted."

Hayes was at the scene with officials Saturday, sorting through the men's gear to determine whether all parts had been functioning properly.

"Like most accidents, most of the time it's human error," he said. "I doubt there's an equipment problem here, to be honest." But he stressed that authorities are still investigating.

The two men had successfully completed two other jumps Saturday morning with 20 other people. But when they didn't return from their third jump, their disappearance led to a search, Pasco County sheriff's spokeswoman Melanie Snow said.

The men were with a group that travels to Florida every year to jump, Hayes said.