VLADIVOSTOK, Russia, Dec. 19 (Xinhua) — At least 21 people have died of alcohol poisoning after consuming a surrogate alcohol liquid in the east Siberian city of Irkutsk, the Russian news agency TASS reported on Monday.

They were among the nearly 40 people locally hospitalized in grave condition.

The report said all of them got poisoned after consuming the liquid. Health authorities have found methanol in tests. Police are searching for shops selling the liquid, it is reported.

Poisonings caused by surrogate alcohol are often seen in Russia, but the Irkutsk case is the among deadliest in years.

Russian authorities have started a criminal investigation into the incident.