An attempted murder-suicide in Asbury Park has left one man dead and another in extremely critical condition outside a First Avenue home Thursday afternoon, according to Monmouth County authorities.

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First Assistant Monmouth County Prosecutor Marc LeMieux told NJ.com a 20-year-old man shot a 30-year-old city man in the head, then turned the gun on himself when police arrived and ordered him to drop the weapon.

The men knew each other and had an ongoing dispute, according to LeMieux.

The victim, with a bullet wound to his head, flagged down an Asbury Park police officer stationed at a construction job near Asbury Avenue shortly after 12:30 p.m., LeMieux told NJ.com.

When police and members of the prosecutor's office arrived at the First Avenue home, the alleged shooter had a gun to his head and pulled the trigger, killing himself as authorities approached him, according to LeMieux.

Authorities have not released the identities of the men.

Anyone with information about Thursday's incident is asked to call Detective Scott Samis with the Prosecutor's Office at 800-533-7443, or Asbury Park Detective Steven Ramseur at 732-502-4587.