Authorities determine cause in Chandler explosion that injured 4

PHOENIX — An unintentional natural gas leak was the cause of an explosion at a printing shop in Chandler that injured four people, authorities said Tuesday.

The blast at Platinum Printing, located at the northeast corner of Ray and Rural roads, was deemed accidental and not criminal, according to a Chandler Police Department press release.

A response crew from the Bureau of Alcohol, Tobacco, Firearms and Explosives determined that the fuel-air mixture explosion that occurred Thursday at 9:23 a.m. was caused by the gas leak and was ignited by “an independent ignition source,” police said.

WATCH: Chandler Police released more video of last week's explosion at Platinum Printing. pic.twitter.com/dmQeEwF3DF

— KTAR News 92.3 (@KTAR923) August 31, 2021

Andrew Ryan, 39; Dillon Ryan, 29; Parker Milldebrandt, 29; and Glenn Jordan, 58, were still receiving care at a hospital, according to police.

Jordan was inside the adjacent EyeGlass Repair business during the blast while the other three were inside the printing shop.

Dr. Kevin Foster, director of the Arizona Burn Center at Valleywise Health, said in a video press conference Thursday that two of the patients were in the ICU and in critical condition, and two were in serious condition. He said they had burns ranging from 16% to 30% of their bodies.

The explosion scattered debris and closed nearby businesses and roads for an extended period.

A witness told ABC15 he heard and felt the explosion from his home half a mile away.

Children at the Maxwell Preschool Academy, which is on the opposite end of the strip mall from the explosion site, were evacuated to the Sunrise Preschool on the northwest corner of Rural and Ray, police said.

The emergency response included more than 100 personnel, according to police.

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