YOSEMITE NATIONAL PARK, Calif. (AP) — The two men who fell to their deaths while climbing El Capitan at Yosemite National park over the weekend were elite climbers who partnered on routes since their college days in San Diego, family and friends said.

Jason Wells, 45, and Tim Klein, 42, were about 1,000 feet (300 meters) up the so-called Freeblast Route when they fell on Saturday, the National Park Service said.

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Brady Robinson, a fellow climber and close friend of Wells, said that the pair last month scaled two El Capitan routes in one weekend. Each climb usually takes skilled climbers several days to complete, Robinson told the Washington Post in a story published Monday.

The two were “simul-climbing,” a technique in which both climbers are attached by a rope and move at the same time to go climb faster, he said.

Robinson, who is the executive director of the Access Fund, an organization that works to protect climbing access, said the pair had invited a third climber to join them on the ascent of the 3,000-foot (914-meter) granite formation and were not going as fast as they could have.

“They were not pushing the envelope,” Robinson said.

Their friend, identified by Robinson as Kevin Prince, made his climb clipped to a separate rope and anchor.

The section of the route where the duo fell was a relatively easy part of the ascent but chunks of rocks can occasionally become loose, Robinson said.

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The cause of the fall is under investigation by the Park Service.

A crowd of people had gathered in the valley below following a rumor that rock climbers Alex Honnold and Tommy Caldwell would attempt a new speed record on the Nose route of El Capitan.

The two did not climb on Saturday but Robinson said there were likely several people “poised with binoculars, just watching” when Wells and Klein fell Yosemite National Park rangers received several 911 calls reporting the fall at about 8:15 a.m. Saturday.

Klein was a teacher from Palmdale, California who twice won his school district’s teacher of the year award.

His widow, Jennifer Tamura Klein, described Klein and Wells like “brothers.”

“When you climb together you really do develop that trust and that love for each other,” Tamura Klein told KTLA in Los Angeles.

Wells was a Boulder, Colorado asset fund manager and is survived by his wife, Becky Wells, and a daughter from a previous marriage, Robinson told the New York Times.

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“They were part of a very small, elite group of people who could do what they did,” he said. “And they weren’t trying to prove anything — they just loved it.”