Irina Andrianova quoted the Chinese general consulate in the Russian Far Eastern city of Khabarovsk as saying that on June 5 a cylinder containing unidentified gas "disintegrated" causing a gas leak in the town of Qiqihar in the Heilongjiang province.
"Local authorities and environmental experts disposed of the cylinder and dealt with the consequences of the accident," she added.
The official quoted the Chinese side as saying that air, water and soil samples taken immediately after the accident contained no contaminants.
Russia's Natural Resources Ministry earlier sent a note to China over the spill requesting official information from the Chinese side as to the location, the cause of the spill and the type of chemicals that could have leaked into the surrounding area.
A local administration source in China earlier said the spill, which occurred some 400 kilometers (some 250 miles) from the Russian border, was caused by a WWII ammunition explosion.
The town of Qiqihar lies along the Nin River, a major tributary of the Songhua River, which flows into Russia. The reports have provoked fears in the province of a major environmental disaster.
Russian Prime Minister Vladimir Putin ordered that the Ministry of Emergency Situations monitor the environmental situation in the region and involve Defense Ministry resources if needed.
"Air monitoring has been arranged. Water in the Amur River is also being tested for contaminants," a spokesperson for the emergencies ministry said.
A November 2005 explosion at a plant owned by the Jilin Petroleum and Chemical Company caused 100 metric tons of potentially lethal benzene to spill into the Songhua River.
The spillage caused substantial environmental damage in Russia's Far East, as a huge slick of chemicals was carried along the Amur River, eventually spilling into the Sea of Okhotsk. China delayed informing Russia about the incident for several days.
