71-Year-Old Man with a Brain Tumor Gets Violently Attacked While Walking His Dog By Charlotte Phillipp

A 71-year-old Arizona man, who was diagnosed with a brain tumor 16 years ago, was violently attacked while walking his dog — and now, his daughter is thanking the two strangers who stepped in to intervene.

Jeff Zimmerman was out in Phoenix on Dec. 13 walking the family dog in his neighborhood when someone on a bicycle approached and began beating him, knocking him to the ground, his daughter Kiera told AZFamily.

The attack nearly killed Zimmerman, Kiera said, but two passersby stopped and pulled the suspect off him.

“But the fact that they were like, right place, right time is literally an act of God. Like, that’s incredible. He’s okay because of these two strangers that happen to be there at the right time,” she told the outlet.

In a GoFundMe page that is raising funds to help pay for Zimmerman’s medical and living expenses, Kiera wrote that “if it were not for the brave couple who stepped in and physically pulled the attacker off my dad, he would not be alive today.”

“They saved his life,” she wrote.

Police in Phoenix told AZFamily that charges have been filed in the case, but authorities have not publicly named the suspect or released information about the investigation.

The Phoenix Police Department did not immediately respond to PEOPLE’s request for further information on the investigation on Dec. 21.

Zimmerman was already dealing with health difficulties due to his brain tumor, Kiera wrote, and the assault has partially exacerbated some of his issues, including an eye injury. He also sustained severe head injuries and multiple broken bones, and spent spent four days in the intensive care unit before being transferred to the trauma unit.

“Given his age and seriousness of his head injuries, doctors have had to monitor him extremely closely,” she wrote on GoFundMe. “He is in immense pain and is only at the very beginning of what will be a long and difficult recovery.”

Speaking to AZFamily, the proud daughter described her dad as her “ride or die” and “strongest person I’ve met in my life.”

“He’s had all the surgeries you can imagine, all the treatments, pretty much my whole life,” she said, adding, “My very first memory is in the hospital with him.”

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Zimmerman’s family said that they estimate his medical costs, related to both the attack and his tumor, will exceed $200,000, and they expect a long road to recovery ahead.

“I can’t even be upset because I’m just so thankful that he’s alive,” Kiera told AZFamily.

“Despite chronic headaches, vision problems, and balance issues, he remains the funniest, craziest, most spirited soul alive,” she added on GoFundMe. “He is strong, kind, and endlessly loving. He lights up every room he enters and continues to inspire everyone around him.”

As of Dec. 21, the Zimmerman family has raised more than $30,000 of the $35,000 goal on GoFundMe.