LONDON (AP) — Former Prime Minister Boris Johnson returns Thursday for a second day of testimony in Britain’s public inquiry into the COVID-19 pandemic, where he is expected to be grilled about how he dealt with the latter stages of the crisis.

Johnson, who is testifying under oath, admitted Wednesday that he made mistakes in grasping the extent of the pandemic and that his advisers failed to sound a “loud enough klaxon of alarm” about the virus.

“I was not being informed that this was something that was going to require urgent and immediate action,” he said, adding that the “panic level was not sufficiently high.”

His remarks came after weeks of testimony by other ministers, including former Health Secretary Matt Hancock, who said they sought to raise the alarm inside the government. Hancock argued that thousands of lives could have been saved by putting the country under a lockdown a few weeks earlier than the eventual date of March 23, 2020.

The United Kingdom went on to have one of Europe’s longest and strictest lockdowns, as well as one of the continent’s highest COVID-19 death tolls, with the virus recorded as a cause of death for more than 232,000 people.

The inquiry is designed to uncover the lessons of COVID-19 to help officials better respond to future pandemics, but its revelations could further tarnish Johnson’s battered reputation.

Johnson, who was celebrated for delivering a landslide victory for his Conservative Party in 2019, was forced to resign as prime minister last year following a series of scandals, including revelations about boozy parties at his Downing Street offices while the country was locked down during the pandemic.