'Bachelorette' Alum Jason Tartick Finds Neighbor Bleeding After Fall, Calls 911

Jason Tartick experienced a near heart-stopping moment when he walked outside his home to take a call ... only to discover his neighbor sprawled on the ground, bleeding and unable to get up.

"The Bachelorette" alum shared the tale Monday ... his next-door neighbor, Bert, who Jason says is battling stage 4 bone cancer, had been lying on the ground for more than an hour -- and he immediately realized the situation was dire.

Jason says Bert was struggling to move, and also was bleeding from his head.

He wasted no time running to help his neighbor and dialed 911. In Jason’s video you can see an ambulance and fire truck on the scene shortly before first responders took Bert to the hospital.

Jason captioned the video, “Praying for Bert. I also never take calls outside, just randomly went out there for a call. Thank God I did.”