Modesto pot deal turns into robbery outside Big Lots. Then witness violently intervenes.

A man who went to the Big Lots store on Oakdale Road on Sunday afternoon to sell marijuana from a duffel bag was assaulted by his customer, Modesto police report.

Delhi resident Rex Petersen, 50, met in the parking lot with a man who pulled a handgun during the exchange and struck him in the head, according to an MPD post on Facebook.

A witness decided the appropriate way to help Petersen was to hit the attacker twice with his vehicle, police said. But the armed man got up from the ground and into a dark sedan, whose driver fled the parking lot. The suspect is described as black and in his 30s, said MPD spokeswoman Heather Graves.

Petersen retrieved his bag, which contained about 10 pounds of pot, police said. Officers took the marijuana from the Delhi man, as well as hash, hydrocodone, the hallucinogenic drugs acid (LSD) and "shrooms" (psilocybin), and a loaded handgun.

Petersen suffered a large gash to his head and had to be medically cleared, Graves said. He later was booked into the Stanislaus County Jail on two counts of possession of a controlled substance for sale, possession of marijuana for sale and carrying a loaded firearm with the intent of committing a felony.

The investigation continues as officers work to identify the armed attempted robbery suspect. Asked if the witness who struck the suspect with his vehicle could face charges, Graves said case information will be given to the Stanislaus County District Attorney's Office to make determinations.

Anyone with information on the case is urged to call Stanislaus Area Crime Stoppers at 209-521-4636. Tipsters can email through the Crime Stoppers website, stancrimetips.com. Callers to Crime Stoppers can remain anonymous and may be eligible for a reward.

This story was originally published April 9, 2018 at 9:39 AM with the headline "Modesto pot deal turns into robbery outside Big Lots. Then witness violently intervenes.."