Lynn La/CNET

Sprint has come under fire from the US government over claims that it tacked on excessive charges for court-ordered wiretaps.

The government filed a complaint against Sprint in US District Court in San Francisco on Monday. The complaint says that government agencies, like the FBI and the Drug Enforcement Administration, were allegedly overcharged $21 million for wiretaps by Sprint.

"Sprint inflated its charges by approximately 58 percent," the complaint reads. "As a result of Sprint's false claims, the United States paid over $21 million in unallowable costs from January 1, 2007 to July 31, 2010."

Sprint is one of the largest wireless carriers in the US and at times is required to hand over information to the authorities for investigations. Typically this information is gathered through wiretaps that need equipment installation -- in most cases, the government reimburses this equipment.

However, in its complaint against Sprint, the government claims the carrier submitted "false claims for reimbursement" of expenses accrued with these wiretap equipment installations.

For its part, Sprint says it operated within the bounds of the law and has cooperated fully with the government's investigation.

"Under the law, the government is required to reimburse Sprint for its reasonable costs incurred when assisting law enforcement agencies with electronic surveillance," Sprint spokesman John B. Taylor told CNET. "The invoices Sprint has submitted to the government fully comply with the law."

In the complaint, the government asks for triple damages and unspecified civil fines.