(Photo by JEFFREY HASTINGS) A Nashua police officer arrives at the scene of the fatal stabbing Friday afternoon at 13 Kinsley St. A suspect is in custody in connection with the incident.

NASHUA — A pair of intensive investigations launched six hours apart Friday by Nashua police and members of the Attorney General’s office in response to two separate homicides in the city have led to the arrests of suspects in both cases, officials said over the weekend.

The hectic series of events began around 11:30 Friday morning, when police received several calls reporting that a person had been shot outside the convenience store at the Sunoco gas station at 543 Amherst St.

Upon arrival, officers found a man, later identified as Lee Knoetig, 53, lying unresponsive on the ground with what was determined to be a gunshot wound to his chest. A short time later, Knoetig was pronounced deceased at the scene, state and local officials said.

The hunt for the suspect came to fruition Saturday, when the Attorney General’s office announced the arrest of Nashua resident Alexander Wheeler, 19, who was charged with one count of second-degree murder.

Meanwhile, at about 5:20 p.m. Friday, roughly six hours after the incident at the Sunoco station, police were called to 13 Kinsley St., a large, four-unit apartment building between Elm and Walnut streets, by a caller or callers who discovered the body of an apparently deceased woman in one of the apartments.

(Photo by JEFFREY HASTINGS) The apartment building at 13 Kinsley St. that became a crime scene Friday afternoon with the discovery of a deceased woman in one of the apartments is cordoned off by police tape.

Arriving first responders confirmed that the woman, identified as Julie Graichen, 34, was deceased, and it was later determined that she was stabbed to death, investigators said.

Early Sunday, the Attorney General’s office announced the arrest of Miguel Ramirez, age 30, of Nashua, who was charged with one count of second-degree murder in connection with Graichen’s death.

Both Wheeler and Ramirez are scheduled for arraignment today in Hillsborough County Superior Court South, officials said. Although suspects charged with such serious offenses as murder are almost always ordered held without bail — and therefore waive formal arraignment — they can choose to appear before the judge and argue bail, or ask the judge to schedule a hearing to address the matter of bail.

As for the fatal shooting, an autopsy performed by chief state Medical Examiner Dr. Jennie Duval determined that the cause of Knoetig’s death was a gunshot wound to the chest, and the manner of death is homicide.

The second-degree murder charge accuses Wheeler of “recklessly causing the death of Mr. Knoetig under circumstances manifesting an extreme indifferent to the value of human life, by shooting him,” according to the AG’s office.

(Photo by JEFFREY HASTINGS) Two Nashua police officers take up position outside the Sunoco gas station, 543 Amherst St., on Friday, shortly after police arrived for a report of a shooting. One man was killed and another is in custody.

Police taped off a perimeter around the Sunoco station as detectives began to arrive, drawing the attention of people at other businesses in the area. The station, owned by TRAK Energy, based in Westborough, Massachusetts, is on the north side of Amherst Street diagonally across from Capitol Street.

Detectives and uniformed officers spoke with numerous people in the area, asking them whether they heard a gunshot or happened to see the verbal altercation that preceded the alleged shooting.

Investigators also reviewed images captured by security cameras from the Sunoco station and neighboring businesses.

Officials haven’t gone into much detail regarding the circumstances that led up to the shooting, but indications are that Knoetig and Wheeler knew each other, at least to some degree. It’s believed an argument preceded the alleged shooting, but the topic or topics of the argument aren’t yet known.

Officials didn’t say where they caught up to Wheeler and arrested him; they described him as a Nashua resident but didn’t provide a street address.

Alexander Wheeler, 19, of Nashua

As for the Friday afternoon stabbing death, details as to the circumstances surrounding the series of events haven’t yet been provided by officials, other than the identities of the suspect and alleged victim.

Among them is whether Ramirez and Graichen knew each other, and if so, what their relationship was. Officials also haven’t indicated whether the alleged stabbing was a random act.

Investigators worked within a wide, taped-off area in and around 13 Kinsley St. well into Friday night and into Saturday, keeping everyone, including the building’s other residents, away from the scene for the time being.

Also off-limits for a period of time were parked vehicles belonging to the tenants and some neighbors that were included in the taped-off area.

Anyone who has any information that may assist police in the investigations of both incidents is urged to report the information by calling the department’s Crime Line at 589-1665.

(Photo by JEFFREY HASTINGS) Onlookers watch in the background as police officers and detectives discuss evidence and other details of the stabbing death that occurred Friday afternoon at 13 Kinsley St., a large apartment building that is out of the picture at right.

Dean Shalhoup may be reached at 594-1256 or dshalhoup@nashuatelegraph.com.