ANCHORAGE, Alaska » A 191-foot fishing boat suspected of using an illegal high seas drift net to catch a half-ton of salmon in the North Pacific was detained by the U.S. Coast Guard last week and turned over Tuesday to Chinese authorities.

The Yin Yuan was spotted by a Canadian aircraft hosting Japanese observers. It was seized by the Honolulu-based U.S. cutter Morgenthau, which was carrying two Chinese law enforcement officials.

"All these countries are affected by illegal activities," said a Coast Guard spokesman, Petty Officer 2nd Class Grant DeVuyst.

High seas drift net fishing kills huge amounts of fish, birds and marine mammals with nets suspended for miles. The practice is universally condemned, according to the Coast Guard, and is a significant threat to ecosystems.

A Canadian CP-140 maritime patrol aircraft May 22 spotted the Yin Yuan in the North Pacific on May 22. The vessel was carrying equipment associated with large-scale illegal drift net fishing, including net, net buoys and net spreader on deck.

The Morgenthau, a 378-foot Honolulu-based, high-endurance cutter, was patrolling the North Pacific in support of fisheries law enforcement and was carrying two officials from the China coast guard’s Fisheries Law Enforcement Command.

The Morgenthau intercepted the Yin Yuan on May 27 about 625 miles east of Tokyo, near where it was first spotted from the air, DeVuyst said. The vessel’s captain told a boarding team that the Yin Yuan was registered in China.

The captain acknowledged carrying 2.05 miles of nets onboard. He also said the crew had dumped drift nets and other gear overboard before the cutter approached.

The vessel, according to the Coast Guard, used prohibited fishing gear, failed to maintain sufficient catch records and fished with no authorization by a sanctioned authority. The Coast Guard also noted pollution problems.

The Morgenthau escorted the Yin Yuan more than 1,400 miles to a China coast guard vessel in the East China Sea.