BOSTON (AP) – A state senator arrested this week for attempting to grope one woman and making lewd comments to a second was admitted to a psychiatric hospital Thursday.

State Sen. James Marzilli entered the hospital hours after saying he would not seek re-election in the fall. The decision came a day after he was arraigned in Lowell District Court on multiple charges related to the arrest.

Marzilli’s lawyer confirmed that he was seeking treatment.

“Sen. Marzilli was admitted into a local hospital for treatment for an undisclosed illness this afternoon,” said Marzilli’s lawyer Terrence Kennedy. “This has been an extremely difficult time for his wife and family.”

A source close to Marzilli told The Associated Press on condition of anonymity because of the sensitivity of the case that Marzilli was seeking treatment at McLean Hospital, a psychiatric hospital in Belmont.

Marzilli, 50, pleaded not guilty Wednesday to charges he tried to grab a woman sexually at a park in Lowell, then fled police, and to charges he made lewd remarks to another woman.

Charges against him include disorderly conduct, resisting arrest, assault and battery and obstruction of justice.

The Arlington Democrat said in a statement earlier Thursday that his Statehouse staff “will continue to respond to the needs of constituents within the district” until the end of his term.

“Susan and I thank the many of you who have reached out with your love and kindness in the past few days and we ask for your continued good wishes and support during this very difficult time,” Marzilli wrote, referring to his wife Susan Shaer, a longtime political activist and commentator.

Marzilli is free on $1,500 cash bail and due back in court July 3.

A spokesman for the Middlesex District Attorney’s office said investigators were looking into other incidents possibly involving Marzilli, including one last year in Arlington and another in Boston’s Brighton neighborhood two years ago.

Investigators also were looking into whether Marzilli was involved in other incidents in Lowell before his arrest.

Last month, Middlesex District Attorney Gerry Leone declined to charge Marzilli after a woman claimed he had touched her inappropriately in April, saying there was insufficient evidence.

Marzilli was arrested Tuesday after a woman told police he approached her while she was sitting on a park bench and tried to grab her crotch. The woman said she had seen Marzilli a week earlier dressed in raggedy clothes and confused him with a homeless person, prosecutor said.

When confronted by police, Marzilli identified himself as Martin Walsh – the same name of a House colleague – and then fled on foot through downtown Lowell, according to police. He was later arrested in a parking garage.

A second woman called authorities after seeing media coverage of Marzilli’s arrest and said Marzilli made lewd comments to her.

Kennedy said his client “completely and totally denies” the charges.

“I find the whole situation, at least what I’ve read about it, both shocking and sad,” Gov. Deval Patrick said Thursday when asked about Marzilli’s decision not to seek re-election.

Marzilli spent 17 years in the House before winning a special election in December to fill a vacant seat in the Senate. His district includes Arlington, Billerica, Burlington and parts of Lexington and Woburn.

Two other Democrats – Arlington Selectman John Hurd and retired firefighter Kenneth Donnelly – already were running for Marzilli’s Senate seat.

AP-ES-06-05-08 1908EDT