U.S. Markets open in 1 hr 19 mins

Molycorp CEO steps down, interim replacement named

GREENWOOD VILLAGE, Colo. (AP) -- Molycorp Inc. said Tuesday that its CEO Mark Smith has left the company and it has named Constantine Karayannopoulos as interim president and CEO.

The rare-earth minerals company did not disclose the reason for Smith's sudden departure.

Shares of the Greenwood Village, Colo.-based company fell 6 percent in after-hours trading on the news to $10.63.

Molycorp said last month that the SEC is looking into the accuracy of the company's public disclosures, among other things. The company said at the time that it is cooperating with SEC staff but cannot predict the length, scope, results or the impact of the matter.

Karayannopoulos will take on the new job immediately and lead the company while it searches for a permanent replacement. He worked most recently as president and CEO of Neo Material Technologies and currently serves as director and vice chairman of the Molycorp board.

Ross Bhappu, chairman of the Molycorp board, said the company has made significant progress in recent years and the timing was right for a change.

"Molycorp is at a natural inflection point, as it transitions its focus from development to ongoing operations, to bring in a proven business leader with industry experience, a track record of operational excellence and management experience to execute Molycorp's strategy," Bhappu said in a statement.

Its shares have lost over 85 percent of their value since spring 2011 when they peaked at $79.16.