A 21-year-old man was stabbed to death in Ottawa overnight, causing a sprawling crime scene that cut the busy intersection of St. Laurent Boulevard and Ogilive Road in half for hours on Sunday as police pieced together what happened.

Solomon Odekunle has been identified as the man killed, police said. His death marks the city's 17th homicide of 2016.

A 27-year-old man is in custody and expected to appear in court Monday, police said late Sunday afternoon.

Police were called to the scene just before 2:30 a.m., but police tape remained stretched across the usually traffic-heavy intersection late into the afternoon.

Orange and yellow police markers stretch from the Piper's parking lot across St. Laurent to the Coventry median. <a href="https://t.co/A7aPLEDsQ1">pic.twitter.com/A7aPLEDsQ1</a> —@amkfoote

Staff Sgt. Bruce Pirt of the major crimes unit said police are working to determine a timeline of events, and called on any witnesses to come forward.

Investigators know something happened in front of Piper's Bar and Grill, but don't know if it started there, ended there or happened partway through — and can't say yet whether or not a fight spilled out from inside the bar.

Evidence markers surround a blood stain on the pavement outside Piper's Bar and Grill. (Andrew Foote/CBC)

Evidence markers peppered the pavement outside the bar, then curved their way across St. Laurent Boulevard to the Coventry Road median. More markers snaked diagonally through a parking lot near the bar, stopping at Cyrville Road.

"We're not sure if it's all evidence but let's capture it, both on camera and physically, and we'll decide later on what really is evidence and what isn't," Pirt said.

"Right now let's keep the scene big and gather everything we can because we only have one crack at a scene."

Blue and green markers evidence markers pepper a parking lot near Piper's Bar and Grill. (Andrew Foote/CBC)

Pirt said it's a big scene because they have to analyze all the blood and potential evidence, but they're trying to narrow it down.

"We do have some bloodletting that covered quite an extensive area, we have to make sure it's all connected to the same incident," he said.

"As we investigate further we'll be able to tighten up that scene and make it smaller and smaller."

He added that police have been gathering video evidence from "a number of establishments" surrounding the crime scene.

The meridian on Coventry Road is also part of the crime scene. (Andrew Foote/CBC)

Some businesses had to close Sunday due to the large crime scene, including Mobile Pressure Cleaning, which is behind Piper's. Owner Dave Delauniere, who had been at that location since 2008, said he's surprised but doesn't have any safety concerns.

"It's an industrial area, [a] commercial area so no, I've had no problems here," Delauniere said.