Man arraigned for 'seal bombing' Ketchikan tunnel

Joseph Duane Brown, 39, appeared in Juneau court Friday
This 2006 photo shows the tunnel where a man is charged with setting off "seal bombs" on July 4 in Ketchikan.

A 39-year-old man is facing federal charges for possessing explosive materials after allegedly detonating “seal bombs” — normally reserved for scaring seals away from fishing nets — inside the Ketchikan tunnel last month, according to federal prosecutors.


No one was injured in the July 4 incident despite the fact that a taxi cab was driving through the tunnel at the time, Assistant U.S. Attorney Jack Schmidt said.

“It didn’t do any damage (to the tunnel), and it didn’t hurt the person that was in the tunnel at the time,” Schmidt said in an interview.

Schmidt said the defendant, Joseph Duane Brown, a Ketchikan resident originally from Juneau, used Tannerite, a type of binary exploding rifle target commonly used in shooting practice, to set off the bombs.

“Basically what he did is he had 20 pounds of Tannerite, and he got 20 seal bombs and he mixed the — it’s a binary explosive, so you have to mix it with aluminum shavings to make it go off — and then he stuck seal bombs in bags, one-pound bags of Tannerite, daisy chained it together with a fuse and then lit it and ran,” the prosecutor said.

Because Brown is a convicted felon, he is prohibited from possessing explosive materials. He is facing a sole count of “receipt and possession of explosive materials by a prohibited person,” a felony that can carry up to 10 years in federal prison.

A federal grand jury in Anchorage indicted Brown on that sole charge last month. The indictment was unsealed after Brown was found and arrested Wednesday on Duke Island.

He pleaded not guilty Friday during an arraignment in U.S. District Court in Juneau. He was appointed a federal public defender and scheduled to stand trial in October.

Bureau of Alcohol, Tobacco, Firearms and Explosives agents from Anchorage flew to Ketchikan to investigate the incident. They recovered the remaining materials and analyzed them.

ATF regulations list seal bombs as perchlorate explosive mixture, but they are legal to own with the proper license, according to Schmidt. Seal bombs are about the same size as firecrackers. Tannerite is listed as a cap-sensitive ammonium nitrate explosive mixture.

According to the indictment, Brown has six prior convictions out of Ketchikan for various offenses including second-degree burglary and second-degree theft.

The 274-foot tunnel located in downtown Ketchikan is a curious attraction and a local historical landmark, perhaps because a street winds around it. It was constructed in 1954.

• Contact reporter Emily Russo Miller at 523-2263 or at


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