Four people are injured and a fifth is in custody after four separate attacks in Vancouver on Thursday morning.

Police were called to the area of Cambie Street and West Broadway shortly after 8:30 a.m., where they found a bike courier stabbed and bleeding heavily.

Witnesses at the scene tell CTV News an off-duty doctor from a nearby clinic administered first aid to the bleeding victim, and the person was still conscious before being taken to hospital.

Police taped off the northwest and northeast corners of West Broadway, and placed a blue tarp over a shopping cart. Multiple police units were on scene and bloody clothes were visible on the ground.

Meanwhile, the suspect fled eastbound to Yukon Street, where he physically assaulted a second person, police said.

A third was stabbed a short time later near Quebec Street and East 4th Avenue, and a fourth was stabbed at Main Street and East 2nd Avenue.

Witness Tony Spence was waiting at a bus stop in the area and saw one victim get stabbed in the neck. He described the assailant as a man with dark, unkempt hair who was carrying a Bible.

"He walked up behind the gentleman and did something to his neck," Spence said. "Then all of a sudden this lady was like, 'He's bleeding!'"

The stabbing victim was conscious and didn’t appear to be critically hurt, Spence said.

The attacker walked away, but Spence followed a safe distance back. Another man joined him and called 911, and police arrived shortly after and took a man into custody near Quebec Street and 2nd Avenue.

Const. Jason Doucette said the suspect is a 33-year-old Vancouver man, who was arrested without incident, is believed to be responsible for all four attacks. He remains in police custody.

The three stabbing victims remain in hospital in serious condition. Police have not provided information on the other victim, who was physically assaulted but not stabbed.

Officers ask witnesses of any of the assaults, who have not yet spoken to police, to call detectives at 604-717-2541.