ARLINGTON — Detectives continue to study financial records for the former director of the Snohomish County Emergency Radio System, a man accused of using taxpayer money to swag out his house.

New court papers show investigators have compiled seven pages of spreadsheets listing items that Mark S. McDermott allegedly bought for himself with public money. The questioned purchases go as far back as 2011 — years earlier than initially suspected.

“Those were all purchases on the SERS dime that we believe he purchased for personal benefit,” Lynnwood police Cmdr. Steve Rider said Friday. “The list of items contained in the spreadsheet is not an exhaustive list. We believe there’s much more.”

McDermott, 64, has not been charged with a crime. He is under investigation for felony first-degree theft and first-degree possession of stolen property.

McDermott was fired in October from the county’s emergency radio system, known locally by the acronym SERS. The tax-funded agency oversees some $25 million in public safety equipment, including the handheld radios carried by police and firefighters for emergency communication.

Two weeks after McDermott was fired for dishonesty, problems were discovered with SERS invoices, and Lynnwood police were asked to investigate.

The detectives served two search warrants on McDermott’s Arlington-area property last year. With a judge’s permission, they have returned twice in recent weeks, seizing dozens of additional items. The total value of potentially stolen property is believed to be in the tens of thousands of dollars.

McDermott’s questioned spending included $2,929 for welding equipment, $4,473 at a tractor supply store, $8,870 at The Home Depot and $8,770 at Lowe’s, according to a police affidavit obtained by The Daily Herald.

Among the purchases were tools and tool chests, indoor and outdoor light fixtures, fencing, a bronze doorbell and a $400 kitchen faucet with a motion sensor.

There also were lawn mower attachments, a storage shed, 475 pounds of grass seed and landscaping software worth $445.

“Landscaping is not something that SERS does,” Lynnwood detective Scott Dilworth wrote in the affidavit.

McDermott also reportedly used a SERS account to pay for $976 in repairs to his personal Chevrolet Suburban and for $1,500 on motorcycle speakers and related audio upgrades. A motorcycle was seized from McDermott’s property in February, records show.

A business associate of McDermott’s reportedly told police that he sold three generators for McDermott and helped him buy a tractor. The man received “a $1,500 kick back” for his efforts, Dilworth wrote. The new court documents say McDermott took one of the missing generators from an emergency radio tower site.

Earlier in the investigation, detectives had focused on a gravel road that McDermott built last year. About 100 tons of gravel had been acquired, purportedly for SERS. A SERS-owned aerial drone, the kind used to take pictures, remains in police custody as potential evidence.

McDermott reportedly also bought firefighting clothes with SERS money, including boots, shirts and pants. None of the clothing had been distributed to employees.

Police showed one SERS employee photos of the clothes.

“Once (the employee) saw the photos of the pants, he realized McDermott had been wearing them,” Dilworth wrote.

Rikki King: 425-339-3449; rking@heraldnet.com.