Just a few days after seven states joined the US Justice Department's suit against AT&T's proposed merger with T-Mobile; wireless carrier Cellular South filed an antitrust suit in the District Court for the District of Columbia seeking to stop the controversial deal.

Based in Florida, Cellular South is the largest privately held wireless carrier in the country. Cellular South has around 900,000 customers and has CDMA roaming contracts with Verizon Wireless and Sprint. It also offers GSM coverage.

In its complaint, Cellular South argued that the proposed merger of AT&T and T-Mobile could even result into the extinction of regional carriers.

The carrier added that regional carriers would not be able to get the latest wireless devices in time as the whole market would concentrate into the hand of the two largest carriers, viz. AT&T and Verizon Wireless.

Cellular South's antitrust suit followed joining of U. S. Department of Justice's suit against the merger by seven states: New York, Washington, Pennsylvania, Illinois, California and Massachusetts and Ohio.

AT&T/T-Mobile's proposed $39 billion transaction, if approved, will create a merged entity that will surpass Virgin to become the biggest telecommunications firm in the US.