Six hours after the fact, Las Vegas homicide detectives worked to reconstruct the scene of a shooting Tuesday that left one man dead in the southeast valley.

Las Vegas police investigate a fatal shooting in the 5700 block of Boulder Highway, near Tropicana Avenue, on Tuesday, Jan. 8, 2019. (Rio Lacanlale/Las Vegas Review-Journal)

Las Vegas police investigate a fatal shooting in the 5700 block of Boulder Highway, near Tropicana Avenue, on Tuesday, Jan. 8, 2019. (Rio Lacanlale/Las Vegas Review-Journal)

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Six hours after the fact, Las Vegas homicide detectives worked to reconstruct the scene of a shooting Tuesday that left one man dead in the southeast valley.

About 12:15 a.m., the Metropolitan Police Department began receiving 911 calls reporting that a man in his 40s had collapsed in the roadway on the 5900 block of Boulder Highway, near East Tropicana Avenue, homicide Lt. Ray Spencer said.

Officers found two injured men — one suffering from at least one gunshot wound and the other suffering from substantial facial injuries, including a broken nose and a possible broken cheek bone, Spencer said.

Both men were taken to Sunrise Hospital and Medical Center, where the man who was shot was pronounced dead about 6 a.m., marking Metro’s first homicide investigation this year.

By 7 a.m., the daylight and yellow tape stretching across Boulder Highway between Bend Street and English Avenue revealed an hours-old crime scene.

Spencer said the shooter had made plans to meet a woman in the parking lot of a business near Boulder Highway and Bend Street. When the man arrived on his motorcycle, he found her arguing with the man who died and immediately attempted to gather the woman’s belongings so they could leave.

“At that point,” Spencer said at the scene, “the other male began to engage him in a fight.”

During the altercation, the man who had arrived on the motorcycle opened fire in what police have preliminarily called an act of self-defense.

The man who was shot attempted to run but collapsed in the roadway shortly thereafter, Spencer said. The woman also left the scene before officers arrived.

As of 8:30 a.m., homicide detectives had not been able to locate the woman or any witnesses, “so we have not been able to corroborate any of the details that have been provided to us from the shooter,” Spencer said.

Anyone who may have witnessed the incident is asked to contact Metro’s homicide unit at 702-828-3521 or, to remain anonymous, Crime Stoppers at 702-385-5555.

The man who was killed will be identified by the Clark County coroner’s office after his family has been notified of his death.

Contact Rio Lacanlale at rlacanlale@reviewjournal.com or 702-383-0381. Follow @riolacanlale on Twitter.