NEW YORK (CNN/Money) - Media conglomerate Viacom Inc. may be broken into at least two different publicly traded companies, separating its cable and film assets from its broadcast television and radio business, the company announced Wednesday.

Rumors of a potential split began circulating late in the afternoon, pushing Viacom (up $2.13 to $36.00, Research) shares up more than 8 percent to close at $37.05 on the New York Stock Exchange. The stock continued to rise in after-hours electronic trading on INET.

Chairman and Chief Executive Sumner Redstone and the company's board has been exploring the possibility of dividing the company as a way to boost the value of its stock, Viacom said in a statement.

"It is clear that... Viacom's businesses have inherently different growth characteristics and investment attributes that appeal to different types of investors," said Redstone.

"It has also become clear that this important distinction is likely to continue to limit Viacom's ability to receive full value for its assets and its prospects in the investment community," he added.

In his remarks, Redstone indicated that one company could include the MTV cable networks and be led by current Viacom co-president, Tom Freston.

The other company, Redstone said, would likely combine CBS broadcast business and Infinity radio operations and be headed by Viacom's other co-President Leslie Moonves.

"The transaction should also enable us to retain the best people for each business and would provide incentives for the creation of shareholder value that are more closely tied to the businesses they run," Redstone said.

Viacom is a leading global media company that covers broadcast and cable television, radio, outdoor advertising and online businesses.

The company's best-known brands include CBS, MTV, Nickelodeon, Paramount Pictures, Infinity Broadcasting, and Simon & Schuster.