YAKIMA, Wash. -- The extent of weapons, drugs and money seized last week is large enough that authorities are considering treating it as a federal case of domestic terrorism.

Thirty-three guns, including two fully automatic weapons, $85,000 in cash, three pipe bombs and hundreds of marijuana plants were seized last Wednesday inside two homes and a storage unit in Yakima.

Police linked all the sites to a 35-year-old Yakima school janitor. Drug charges have been filed against Kevin Michael Kuntz in Yakima County Superior Court, where he's expected to face charges later this week in connection with the pipe bombs.

But the case will be referred to federal investigators because of the bomb-making material and the three live pipe bombs, said Chief Sam Granato, who called it a possible case of domestic terrorism.

"What other reason would people be making bombs for?" Granato said Monday afternoon. "Generally you don't have mercury switches and bomb pipes just laying around the house. That's something that needs to be investigated."

Jessie Summers, a Bureau of Alcohol, Tobacco Firearms and Explosives special agent in Yakima, said his agency will be involved in the case's prosecution.

"We're going to try to take some of those guys federally at YPD's request," he said.

It is unclear how many people are involved in the operation. Yakima police Lt. Tom Foley said during a news conference Monday that three or four other people have been arrested in connection with the case.

Their status, however, was unclear Monday.

At Monday's news conference, police displayed weapons from the raid along with dozens of others confiscated in separate and unrelated gang investigations from recent months.

Among last Wednesday's seizures were an MAC 11 -- a machine-gun pistol -- several AK-47s, homemade silencers, shortened AR-15 rifles, shotguns and a bag full of rolled-up $100 bills.

It began as "a simple dope case," Foley said.

On Wednesday, YPD narcotics officers stopped a vehicle suspected of being involved in transporting drugs to Tacoma. Inside, they found several large freezer bags full of pot -- and $41,000 in cash, authorities said.

Information from there led officers to more drugs, cash and weapons at two homes in the 900 block of South 18th Avenue and the 1100 block of South 20th Avenue and a storage unit in the 3000 block of Castlevale Road.

Granato said Kuntz lived at the 18th Avenue home and may have rented the other two.

Kuntz was charged last week with possession and manufacturing of a controlled substance with intent to deliver, in connection with the 900 indoor marijuana plants and 36 pounds of manufactured marijuana.

A Yakima School District spokeswoman confirmed Monday that Kuntz is a custodial employee for the district but could not immediately say what school he works for.

A man who answered a phone at another residence where Kuntz is listed in the telephone book declined to comment for this story.

* Melissa Sánchez can be reached at 509-577-7675 or msanchez@yakimaherald.com.