(Photo : GoFundMe)
Aleia Lopez was killed by a giant steel cylinder while she walked down a sidewalk.

A Pittsburgh mother of three was killed in a freak accident when a giant steel cylinder fell on her while she was walking on a sidewalk.

It happened around 10:30 a.m. Friday near the Petersen Events Center.

Aleia Lopez had "significant, grave injuries to her head," according to police.

She was pronounced deceased at the scene a short time later.

Witnesses said Lopez, who works at a nearby hospital, was walking with her colleagues when a large steel cylindrical drum broke free from a nearby construction site.

Police say the drum rolled down a hill within the construction site, went through adjacent construction fencing, and hit her.

The drum continued to roll across the street before finally coming to rest against a pickup truck.

Bystanders attempted to perform lifesaving measures on Lopen before medics arrived.

Melanie Hall was raising money on a GoFundMe page to pay for Lopez's funeral and support her three children Angelia, Leilani and Ethan. It had more than $25,000 in donations by Saturday.

"Aleia was a light in the lives of all that knew her and the rock for her three children," Hall said.

She told WPXI-TV that her daughter had been on a lunch break from her job at Western Psych at the time of the accident.