WASHINGTON (AP) — Rep. Jesse Jackson Jr. admits to “his share of mistakes” his resignation letter to House Speaker John Boehner and acknowledges an ongoing federal investigation.

The Illinois congressman resigned on Wednesday after being on a months-long medical leave for bipolar disorder. His resignation comes just two weeks after voters re-elected him to a ninth full term and amid reports of a new federal probe into possible misuse of campaign money.

In his letter, Jackson says he is doing his best to address the situation responsibility, cooperating with investigators and “accept responsibility for my mistakes.” He also says his constituents “deserve a full-time legislator in Washington,” something that wasn’t in his future because of his health issues.

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