BERRIEN COUNTY, Ind. -- A 45-year-old Niles man is dead after his motorcycle was struck from behind Thursday afternoon, according to authorities.

The Berrien County Sheriff's Office reports deputies responded to W. US 12 and Lubke Road in New Buffalo Township around 12:30 p.m. for a multi-vehicle crash.

Deputies arrived to find a motorcyclist had been struck from behind and was suffering from life-threatening injuries.

The motorcyclist was treated on scene before being taken to Franciscan Hospital in Michigan City for surgery. He later died from his injuries.

The man's identity is being withheld pending next of kin notification.

Investigators determined via testimony from witnesses that the motorcyclist was nearly stopped on the W. US 12 going west with his left turn signal on waiting to turn left onto Lubke Road. That's when a minivan, driven by a 39-year-old Sedalia, Missouri woman, also traveling west, failed to notice the motorcycle slow in front of her.

The minivan then and struck the motorcycle from behind ejecting the man.

After striking the motorcycle, the minivan's driver lost control, crossed eastbound traffic lanes, and struck the side of another vehicle.

The woman driving the van suffered minor injuries but declined medical treatment at the scene.

The other driver was uninjured.

The motorcyclist was not wearing a helmet at the time of the crash.

Authorities say drugs nor alcohol appear to be factors in this crash.

Both directions of US 12 were closed for about two hours while the crash was investigated.

The investigation remains ongoing.