Frontier Communications, which entered the Triangle market through a deal with Verizon in 2010, is buying more Verizon assets in a deal worth nearly $10 billion plus debt. 

Verizon announced two deals on Thursday bwhich it says will produce some $15 billion for the wireline assets and in a wireless tower leasing deal.

The largest U.S. cellphone carrier is selling its California, Florida and Texas wireline businesses, which serve telephone, TV and Internet customers, to Frontier Communications  for $9.9 billion in cash. Frontier is also taking on $600 million in debt.

Verizon says it wants to concentrate on the East Coast wireline business and will focus on expanding its FiOS broadband and high-speed Internet business in that region.

In 2010, Verizon sold Frontier 4 million phone lines in 14 states for $5.3 billion. Frontier said the newest deal is scheduled to close in the first half of 2016.

That 2010 deal brought Frontier to the City of Durham and Durham County.

Frontier currently is expanding its fiber-optic network in Durham County with an emphasis on the Research triangle and downtown Durham.

American Tower Corp. will pay $5.06 billion to lease 11,300 wireless towers and buy 165 others. It will be able to operate the leased towers for an average term of 28 years, with an option to buy. The company expects to close the deal during the first half of 2015.

New York-based Verizon Communications Inc. said it plans to return some of the cash to shareholders with a $5 billion stock buyback. Its shares rose 1 percent to $48.35 in aftermarket trading.

The moves come almost a year after Verizon took full control of its wireless business, buying out Vodafone Group PLC’s 45 percent stake in a deal valued at $130 billion. The purchase means Verizon no longer has to share its wireless revenue with Vodafone.

Citi Investment Research analyst Michael Rollins said the sales are a positive development for Verizon, and he kept a “Neutral” rating on the stock.

Shares of Stamford, Connecticut-based Frontier Communications Corp. stock rose 26 cents, or 3.4 percent, to $7.96 in extended trading. Shares of Boston-Based AmericanTower Corp. rose 12 cents to $99.71.