Two former employees of a Los Angeles-area ambulance company and a dialysis treatment center pleaded guilty on Monday to a Medicare fraud scheme that ran up nearly $7 million in fraudulent claims, the U.S. Attorney’s office announced Monday.

Aharon Aron Krkasharyan, 53, a former employee of Mauran Ambulance Inc. of San Fernando, pleaded guilty in federal court to one count of conspiracy to commit health care fraud. He is scheduled to be sentenced March 29.

Maria Espinoza, previously employed by DaVita Doctors Dialysis of East Los Angeles, pleaded guilty to one count of conspiracy to pay and receive kickbacks for health care referrals. She is slated to be sentenced on April 2.

Three others connected to Mauran Ambulance have already pleaded guilty for their roles in the same Medicare fraud scheme that resulted in $6.6 million in fraudulent claims for medically unnecessary transportation services, according to federal prosecutors. Medicare paid at least $3 million toward the claims.

As part of their plea agreements, all five agreed to pay restitution to Medicare.

Health business reporter Dana Bartholomew can be reached at [email protected]. Follow him on Twitter @_DanaBart.