Four Oklahoma men Mark and Billy Chastain, Mike Sparks, Alex Stevens missing after bike ride

Four men from a tiny Oklahoma city are still missing days after they all went on a bike ride together Sunday evening, according to authorities.

Mark Chastain, 32; his brother Billy Chastain, 30; Mike Sparks, 32; and Alex Stevens, 29 haven’t been seen or heard from in about four days with little indication where they could be, police said in a Facebook post this week.

The four men were reported missing Monday into Tuesday after they left one of their homes with bicycles in the city of Okmulgee around 8 p.m. Sunday, police said.

Someone claimed seeing the missing men walking on a street around 2 a.m. Tuesday, but police could not confirm that report. Other reported sightings during the week have also not been confirmed, cops said.

Okmulgee Police Chief Joe Prentice told Fox 23 authorities were scouring a salvage yard where the cell phone of Mark Chastain’s was last pinged.

Only two of the men had cell phones on them when they went out, authorities believe, though their cell phones go straight to voicemail.

“The longer they’re missing, the more concerned I am but I have yet to find any evidence that there’s any foul play involved,” Prentice said.

The police department said Thursday in another Facebook post, “We will continue to investigate and are following any evidence we uncover.

Mark Chastain’s wife told Fox News Digital she was heartbroken by the situation.

“I know nothing, and I’m feeling lost. I’m heartbroken. I’m sad. I have so many mixed emotions and thoughts,” Jessica Chastain said.

“As far as I know, nothing has been recovered. Nothing has been found. There is no sign of foul play.”

Okmulgee has a population of more than 11,000 and is roughly 38 miles south of Tulsa.