California regulators imposed $1.13 million in fines on Uber for failing to investigate user reports of drivers who were working while under the influence.

The state Public Utilities Commission’s Consumer Protection and Enforcement Division (CPED) claims Uber breached the agency’s zero-tolerance guidelines for transportation companies that require immediate investigation into consumer complaints of drunken drivers.

Read: Uber Allegedly Shorted Drivers By Manipulating Navigation Data

The CPED said Uber received 2,047 complaints about drivers operating while intoxicated between Aug. 12, 2014, and Aug. 31, 2015. Of those, CPED investigated 154 instances and found the company failed to suspend or investigate 151 reports promptly.

Included in those reports were 89 instances where a driver remained logged into the Uber app for at least an hour after a passenger filed a complaint. In 64 cases, a driver provided one or more rides within an hour of receiving a drunken driving complaint.

Uber provided evidence for just 22 of the investigated instances where it claimed to have suspended the driver within one hour of a passenger filing a complaint — but even in those instances, the CPED reported Uber’s records contradicted claims it had suspended drivers prior to initiating an investigation.

The CPED also reported there were some instances of drunken driving complaints that Uber failed to report to the commission.

In response to the investigation, the CPED recommended Uber be fined for 151 instances of failing to comply with the zero-tolerance rules, each costing the company $7,500 a piece, resulting in a total fine of $1.13 million.

Read: Uber Reportedly Used Exploit To Track And Target Lyft Drivers

Uber responded to the fine by noting the complaints were a couple years old and saying its process for reviewing drunken-driving complaints has improved since then. "We have zero tolerances for any impaired driving," a spokesperson for the company told  Ars Technica.

The fines are just the latest in an ongoing cascade of issues for Uber, which have included recent revelations the company manipulated competitor Lyft’s software, accusations of stealing trade secrets, and reports from former employees of sexual harassment and misconduct within the company.