LEAWOOD, Kan. (AP) — Federal attorneys and a Kansas-based bitcoin company are negotiating over whether the company could resume some of its operations.

The Federal Trade Commission has sued Butterfly Labs, based in Leawood, claiming the company defrauded consumers out of between $20 million to $50 million. Butterfly Labs is under temporary control of a federally appointed receiver.

The Kansas City Star reports that after a hearing Monday, the temporary order was extended and attorneys began negotiations.

The FTC alleges Butterfly Labs did not deliver machines or sent worthless equipment that could not produce bitcoins.

Butterfly Labs has denied wrongdoing and called the FTC action “heavy-handed.”

Bitcoins are virtual currency that is becoming popular as a way to buy and sell some goods and services without using government-issued money.