Drug detectives used two confidential informants, electronic surveillance equipment and thousands of dollars in marked “buy” money to bust twin brothers now charged with dealing marijuana and methamphetamine from the drive-up window of a west Bend taco shop.

Documents filed in Deschutes County Circuit Court on Monday detail a five-week investigation that culminated Thursday night when police seized wads of cash, laptop computers, rifles and a Bible with the center cut out in connection with the suspected sale of drugs from Rigoberto’s Taco Shop.

Damian and Julian Castaneda-Nino, both 23, now face a slew of felony counts, and a judge has frozen two Wells Fargo bank accounts — one held by Rigoberto’s Taco Shop and the other by Damian Castaneda-Nino — and ordered Central Oregon Drug Enforcement detectives to seize the balances.

An affidavit filed by investigators says two confidential informants, motivated by hopes of “leniency” in criminal cases against them, started feeding CODE detectives information about the suspected drug sales in February.

The document says both informants have helped detectives make other drug busts in the past.

They reported that drug deals were going down at Rigoberto’s, generally after 7 p.m., and the transactions happened at the restaurant’s drive-through window.

Officials also had information that Damian Castaneda-Nino was traveling back and forth between Oregon and California “in a red Ford pickup to pick up large quantities of methamphetamine,” the affidavit states.

One of the informants told a drug detective that the deals went like this: The customer would order food, pull around to the drive-through window and tell one of the brothers “that he/she has additional money which will equal whatever quantity of methamphetamine he/she wants. For example, (informant 1) will tell the male ‘I also have $300 dollars’ and the male will then take the money and return with $300 worth of methamphetamine.”

After interviewing the confidential informant, an undercover CODE detective twice went to Rigoberto’s and bought a total of $1,000 worth of methamphetamine directly from Julian Castaneda-Nino, according to the affidavit.

During the second buy, the informant tried to haggle with Julian Castaneda-Nino about lowering the price per gram for a larger purchase, the affidavit reads, but was told “he charges $70 per gram no matter the quantity.”

A second confidential informant twice contacted Damian Castaneda-Nino by phone, requesting to buy a quarter-ounce of meth and then a half-ounce of meth, the affidavit reads.

Both times, investigators used surveillance equipment to listen in on the drug deals before the informant returned with plastic baggies containing drugs.

After each deal, drug detectives used field kits to test the drugs and, each time, the substances tested positive for methamphetamine, according to the affidavit.

During the course of the investigation, the brothers were stopped in two pickup trucks with personalized license plates, one gray with the plate “LAGRIS” and a red truck with a “LAROJA” plate. Each time, they were found with large amounts of cash, the affidavit states.

Investigators regularly saw the trucks parked at Rigoberto’s and two residences where the brothers lived that were later searched.

Inventory receipts filed Monday show that investigators seized thousands of dollars in cash from the twins’ homes, hidden in briefcases, boxes and in closets. Authorities also took rifles, including one assault rifle, a shotgun, drugs and “credit cards in different names.”

At Rigoberto’s, detectives seized a handgun and cash, including $18 in tip money sitting on a counter, according to the inventory receipt.

An affidavit filed with a request to seize the Wells Fargo accounts says authorities found more than $40,000 in currency.

Damian Castaneda-Nino was arrested at Deschutes County Adult Parole and Probation on Thursday, when he went to visit his probation officer regarding a domestic violence charge.

Julian Castaneda-Nino was taken into custody at Rigoberto’s.

Both were arraigned Friday on charges of conspiracy to sell meth, dealing and manufacturing the drug, and selling marijuana.

A grand jury is expected to convene and review the case this week, and the twins are scheduled to return to court Friday.