A U.K. regulator fined and reprimanded PricewaterhouseCoopers LLP and two of its partners for shortfalls in its audits of a British service provider, following increased scrutiny over the practices of the country’s biggest audit firms.

The Financial Reporting Council, Britain’s regulator for accounting and audit, on Thursday penalized PwC and partners Jaskamal Sarai and Arif Ahmad in relation to audits of the 2015 and 2016 financial statements of Redcentric PLC, a Harrogate, England-based company.

PwC was handed a £6.5 million ($8.25 million) fine and a severe reprimand by the FRC. The fine was reduced to £4.5 million because the professional services firm agreed to settle. PwC will have to closely monitor the work conducted by its Leeds audit practice under terms agreed with the regulator.

PwC—one of the “Big Four” alongside Deloitte LLP, Ernst & Young LLP and KPMG LLP—earlier this month announced various measures aimed at overhauling its U.K. audit business.

In the Redcentric case, the PwC failed to detect various fraud risks in the company’s statements, the FRC said. The 2016 financial statements of the company were extensively restated, resulting in a breach of Redcentric’s debt covenants, the regulator added.

“We are sorry that our work fell below the professional standards expected of us,” a PwC spokesman said. “Since the work in question was completed we have taken numerous steps to strengthen processes.”

Redcentric declined to comment.

PwC and its partners applied superficial analytical procedures and failed to conduct a proper analysis of Redcentric’s financial statements, the FRC said. Redcentric in 2017 switched auditors and signed up PwC competitor KPMG.

“The sanctions reflect the seriousness and extent of the breaches,” said Claudia Mortimore, deputive executive counsel at the FRC. In its findings, the FRC noted that for the 2016 audit, significantly fewer hours were charged by senior PwC staff than in previous years, and that a significant amount of work was performed by an undergraduate trainee.

PwC’s Mr. Sarai and Mr. Ahmad received a discounted fine of £140,000 and a severe reprimand. Both partners took part in training that taught them how to comply with certain accounting standards.

The FRC has taken various actions against U.K. audit firms and companies’ internal audit teams, including against KPMG.

U.K. lawmakers and regulators in recent months released proposals for an overhaul of the sector. Another piece of analysis, dubbed The Brydon Review, is set to be presented to a cabinet minister by the end of the year. The U.K. government is expected to respond to the recommendations from regulators and lawmakers in the coming months.

As part of the changes in the U.K. audit industry, the audit regulator will become part of a new agency called Audit, Reporting and Governance Authority.