Traders on Moscow's RTS stock exchange reacted to the U.S. trading, sending the company's shares down 29.49% as of 18:00 Moscow time [14:00 GMT].
Mechel shares plummeted 45.6 % as trading opened on the RTS stock exchange Friday following Thursday's 33% plunge in the Russian company's ADRs on the New York stock exchange.
The company's stock crept up on the RTS at midday Monday after Kremlin aide Arkady Dvorkovich said: "We hope recent events will be a lesson for both the Mechel company and the entire Russian market."
However, fresh criticism of "a steel company" from Prime Minister Vladimir Putin on Monday caused Mechel shares to plummet further.
The prime minister gave new figures at a meeting of the government's presidium. He said coking coal was being sold for 4,100 rubles ($176) per metric ton on the domestic market, and for 1,100 rubles ($47) to offshore companies in Switzerland, which later resold the coal for $323.
"This reduces the tax base, creates a deficit on the domestic market, and pushes up steel prices, which is reflected on the cost of a range of products," Putin said.
Russia's top antitrust regulator had planned to consider the charges against Mechel by August 26, but would move more swiftly to calm the markets, Federal Antimonopoly Service head Igor Artemyev told the Vesti 24 TV news channel on Monday.
"Initially, when we brought charges against Mechel, we planned to make a decision on August 26. But then we decided to make it earlier so as not to create tensions on the stock market," Artemyev said, adding that the company had to be "punished."
The service said earlier in the day it would take no action against the company for the time being.
Mechel vowed Friday to sell coking coal at the same price domestically and abroad, a day after Putin criticized the company for overcharging in Russia.
The latest reports said the Investigation Committee at the Russian Prosecutor General's Office has launched a probe into Mechel's operations.
Mechel CEO Igor Zyuzin, who controls a 70% share in the company, has been undergoing medical tests at a Moscow cardiology clinic since Wednesday.
