David Walliams Under Police Investigation Over New Sex Misconduct Allegations

David Walliams is under criminal investigation in London ... and the allegations police are looking into aren't even the ones that sparked his recent public scandal.

London's Metropolitan Police confirmed Friday they've launched an investigation into allegations of serious sexual offenses against the British comedian ... after several people came forward with new complaints separate from those reported earlier this week.

And that's not all ... detectives are also reviewing the explosive reporting by ITV News and The Guardian to determine whether additional crimes may have been committed.

As TMZ previously reported, multiple women accused the "Little Britain" star of using his celebrity status to pursue teenage girls and young women ... including some who say they first met him when they were just 15.

The allegations became public Tuesday after Walliams lost his legal battle to keep his identity under wraps ... and the fallout was swift, with his talent agency dropping him.

Walliams has strongly denied wrongdoing ... previously declaring, "I am not a sexual predator. I have not broken the law."

Police say specialist officers are supporting those who have come forward ... and are urging anyone else with information to contact authorities.