Olympic swimmer Michael Phelps was arrested Monday for DUI in Maryland after police spotted him speeding down I-95.

The Maryland Transportation Authority tells E! News that Phelps was charged with driving under the influence, speeding and crossing double lane lines within the Fort McHenry Tunnel.

Authorities say that the multiple gold medalist was clocked doing 84 MPH in a 45 MPH zone.

This is Phelps' second DUI arrest, the first occurring in November 2004 when he was just 19.

Phelps later took to Twitter to issue a public apology, which read, "Earlier this morning, I was arrested and charged with DUI, excessive speeding and crossing double lane lines. I understand the severity of my actions and take full responsibility."

He added, "I know these words may not mean much right now but I am deeply sorry to everyone I have let down."

USA Swimming also released this statement: "The news regarding Michael Phelps and his actions are disappointing and unquestionably serious. We expect our athletes to conduct themselves responsibly in and out of the pool."

Phelps has no meets scheduled for the rest of this year, so it's unclear whether any disciplinary action will be taken.