The incident occurred in the Petropavlovsk-Kamchatsky port, about 6,700 kilometers (4,200 miles) east of Moscow, when the gas used for cooling and refrigeration escaped from the ship's freezer plant, regional emergency official Sergei Viktorov said.
A mechanic died on the spot and four fishermen were hospitalized with gas burns, Viktorov said.
The trawler, the Koyo Maru, had been confiscated from Japan for alleged poaching and was now operated by a Russian company.
The serial production of the Russian stealth bomber known as PAK DA (the prospective long-range aviation complex) is to be launched in 2027. The crew of the new bomber aircraft will consist of four people