In Touch has exclusively learned that hours after Backstreet Boys band mate AJ McLean’s wife gave birth to their second baby, he tried to pick up women and drank alcohol at LA’s Riviera 31, a bar inside the Sofitel Hotel, which is across the street from the hospital.

On March 19 at 5:10 p.m., AJ’s wife, Rochelle, delivered their daughter Lyric. But in an exclusive video obtained by In Touch, AJ is seen grabbing the microphone and belting out the BSB hit “I Want It That Way” just hours after that.

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“He showed up around 1 a.m. and it just happened to be Russian karaoke night,” a witness exclusively reveals.

He then began flirting with multiple women. “He was being incredibly inappropriate. He exchanged numbers with at least three girls and even offered one tickets to his Vegas show,” says the witness.

But AJ really crossed the line “when he asked a few of the girls to send him a sexy, nude photo so that he could use it as their contact image in his phone.”

“No one could believe he was acting like this with his wife across the street at the hospital with their newborn baby,” adds the witness.

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The witness says that AJ, a recovering alcoholic, drank whiskey and beer. (AJ spent time in rehab in 2001, 2002 and 2011 for substance abuse. He admitted in 2012 that he relapsed after his wife gave birth to their first child, Ava.)

AJ’s rep declined to comment when asked about his boozing and hitting on women.

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