A pregnant woman found dead in Oklahoma Friday texted her sister that she was afraid the father of her baby would "blow up" because she'd told his girlfriend she was pregnant, NewsOK.com reports.

Lauren Barnes, 20, of Bethany, Okla., sent the text message at 8:34 p.m. Nov. 23 as she waited near a park for Eric Phan — the man police are holding on a murder complaint in connection with the case — according to a court affidavit, NewsOK.com.

Click here for the NewsOK.com report.

An anonymous tip led police to Barnes' shallow grave in Stinchcomb Wildlife Refuge on Friday near where she disappeared. She was five months pregnant.

"She was buried about 3-feet deep and covered up in debris and leaves and dirt," Bethany Police Chief Neal Troutman said at a news conference. "So it wasn't very visible. It would have been hard to find."

A state medical examiner said Barnes died of asphyxiation, KOCO.com reports.

Phan confessed to his best friend that he had choked Barnes and thought he broke her neck, NewsOK.com quoted the affidavit — filed late Friday — as saying.

Meanwhile, about 200 people gathered Sunday to remember the mom-to-be at a candlelight vigil at Eldon Lyon Park in Bethany, KOCO.com reports.

Click here for the KOCO.com report.

"She was happy to be pregnant — very happy. Every time she talked about it, she'd glow — every time," Fashion Burch told KOCO.com. "If she was still around, she'd be like, 'Wow, people care about me that much.'"

Her funeral is scheduled for Tuesday at 2 p.m.

Phan, 20, was arrested Nov. 28 on a first-degree murder complaint in connection with Barnes' disappearance. He remains in the Oklahoma County jail.