Shares of T-Mobile, AT&T and Verizon fell at least 8% after Elon Musk’s SpaceX announced plans to build a mobile network and compete with major telecom companies|@Nasdaq|X

A new major player could be poised to enter the wireless carrier market. Elon Musk’s SpaceX reached an $8 billion deal on Thursday to buy a nationwide spectrum portfolio, according to the Wall Street Journal.

Spectrum portfolios consist of licenses granting access to specific frequency bands across defined geographic regions, providing the airwaves needed to operate a wireless service. SpaceX’s planned acquisition from technology and communications investment firm Grain Management covers licenses in the 800-megahertz band.

The deal still needs FCC approval.

The announcement sent telecom stocks tumbling on Thursday, with all three major carriers suffering steep losses. But companies recovered soon, and US stocks rose on Friday. The Nasdaq Composite and S&P 500 each gained 0.6%, while the Dow Jones Industrial Average climbed 423 points, or 0.8%.

Major indexes ended the week with strong gains.

Shares of T-Mobile, AT&T and Verizon fell at least 8% after Elon Musk’s SpaceX announcement. 

In contrast, cell tower companies gained sharply. Crown Castle rose nearly 16%, American Tower gained more than 9%, and SBA Communications climbed 7%.