A former campaign aide to D.C. Mayor Vincent Gray says he warned Gray of suspicious activity surrounding his 2010 campaign for the city’s top job. 

David Dzidzienyo, who coordinated field operations for Gray’s mayoral run, told The Washington Post he developed concerns in the summer of 2010 about work by dozens of people on Gray’s behalf who were not a part of the official campaign apparatus.

But when Dzidzienyo alerted Gray to possible trouble, he told the Post that Gray replied, “I don’t want to hear about problems. I just want to be the candidate.”

In July, federal prosecutors revealed that Gray benefited from an off-the-books, $653,800 shadow campaign. The parallel effort that unnerved Dzidzienyo appears to be that shadow campaign.

Gray has denied any wrongdoing, but federal authorities continue to investigate him and his campaign. So far, three Gray campaign aides have pleaded guilty to federal charges, though only one of those officials was charged in connection with the shadow campaign.