GLENDORA (CBS) — A man was killed Saturday while trimming a palm tree in Glendora, authorities said.

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Los Angeles County Fire Department personnel responded to a 4:47 p.m. report of a distressed tree-trimmer on West Bennet Avenue near Grand Avenue, county fire department spokesman Mark Savage said.

Upon arriving at the scene, emergency crews were forced to use infrared technology to locate the man in the dense leaves and branches of the tree, Savage said.

“He was calling out for help and someone called us,” Savage said.

“When we got to the scene he was not visible and was hidden in all the palm tree fronds.”

When firefighters were able to reach the man 40 to 50 feet up in the tree, they found him dead. A witness believed the man died of apparent suffocation from an equipment strap, but the official cause of death is pending tests.

Amanda Burden, reporting for CBS2 and KCAL9, spoke to the victim’s stunned family and friends Saturday evening.

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He identified the dead man as 35-year-old Roberto Garcia.

Jesus Rochin was the victim’s co-worker and friend. “He was up there and I heard him yell, ‘Help’ and ‘Call an ambulance.'”

Sgt. Matt Williams said, “It appears that the weight of the heavy palm fronds, all landing on his chest, caused him to suffocate and hard to breathe.”

Burden said the brush was so heavy it took thermal imaging equipment to find Garcia.

Saturday evening, at least one distraught loved one had to be treated by paramedics.

His brother Jesus said, “I’m just devastated right now…he was a good brother.”

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