BEIJING — A chemical leak in China's northeast killed three people, but the accident was contained and did not pose an environmental threat, Russian authorities said Friday.

Eight people were also sickened when the phosgene gas leaked Thursday from a canister that was being dismantled at a plant in Qiqihaer, about 250 miles from the Russian border, Russia's Foreign Ministry said.

The canister and other similar canisters were quickly destroyed, it said.

Phosgene is a colorless, volatile liquid that is highly poisonous. It is used as poison gas, in organic synthesis and in making dyes.

The leak in the city, which sits along a major tributary of the Songhua River, which flows into Russia, prompted alarmed officials in Russia to order continuous monitoring of air and water quality.

The Russian Foreign Ministry said it had received the information from the Chinese environment protection ministry, which had not posted the information on its Web site as of early Saturday.

China's official Xinhua News Agency had only a short report with few details. Telephones at the local police department rang unanswered.

Chinese authorities reported no environmental damage after checking air and soil samples, the Russian ministry said.

A 2005 chemical spill in the Songhua strained China-Russia relations after poisoned water flowed across the border. The spill included potentially cancer-causing chemicals and forced the northeastern Chinese city of Harbin to sever water supplies to 3.8 million people for five days.