LOWELL -- City police are investigating the suspicious death of a woman found inside a Walker Street apartment where officers were sent to check on a potentially suicidal man.

Officers were sent to 255 Walker St. at about 8:50 p.m. to conduct a well-being check on a 52-year-old man whose family called police to report he was "off his meds" and potentially suicidal, according to police radio broadcasts.

Officer Luis Rios was the first to arrive at the apartment. Rios informed dispatchers in radio broadcasts that he found a dead body inside, and immediately requested a supervisor to come to the scene.

Detectives were soon called to the scene as well, and Capt. Kevin Sullivan, the commander of city detectives, left a paid detail he was working to go to the apartment, according to radio broadcasts.

Police radio broadcasts indicated the man police were initially sent to check on, James Sheedy, 52, of Lowell, was not at the scene.

Police distributed a photograph of Sheedy to officers Saturday night and dispatchers said he may be in possession of a knife and may be "armed and dangerous," according to radio broadcasts.

Sheedy was soon located on the ramp from Thorndike Street to the Lord Overpass after he called police and told dispatchers where he was, according to police radio broadcasts.

Detectives draped a red blanket over Sheedy at that location. Sheedy shook violently at times and appeared he may have been crying as he sat on a guardrail, leaning forward, his head between his hands.

Police placed him under arrest. The charges were not released. Police could not immediately comment on the investigation.

At least eight police cruisers were at the scene on Walker Street -- a three-story apartment building between Broadway and Middlesex Street. Police taped off doors to the home and began keeping a log book of everyone who entered or left the building. Officers also ran the license plates of every vehicle in the building's driveway.

Anyone with information is asked to call Lowell police at 978-937-3200 or Crimestoppers at 978-459-TIPS (8477).

Tipsters can remain anonymous, but can receive up to $1,000 for information leading to an arrest.

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