Russian steel and coal stocks plunged after Prime Minister Vladimir Putin called for antitrust authorities to investigate OAO Mechel for its pricing of raw materials in Russia, according to Bloomberg.

OAO Severstal, Russia`s biggest steel producer, tumbled 22.40 rubles, or 4.9 percent, to 436.01 rubles on the Micex Stock Exchange as of 11:31 a.m. local time. OAO Raspadskaya, a coking coal producer, fell 11 percent to 169 rubles. The Micex Metals and Mining Index sank 6.4 percent to its lowest level since October.

Putin criticized Mechel`s billionaire shareholder Igor Zyuzin for not appearing at a meeting with steelmakers yesterday and said the company should be investigated because it sold raw materials in Russia in the first quarter at twice the price of exports.

Mechel`s New York-traded American depositary receipts plunged 38 percent to $22.84 yesterday. The stock lost $14.10, or 39 percent, to $22.50 on Moscow`s RTS Index today. Mechel is more heavily traded in New York than in Moscow.