A 28-year-old Garland man was killed early today in Dallas when his motorcycle slammed into a one-way sign on Northwest Highway near Jupiter Road, police said.

Another motorcyclist was killed in an unrelated accident in Arlington.

In the Dallas crash, the motorcyclist – who was not identified pending notification of relatives – was traveling west on Northwest Highway, in the inside lane, when he lost control of his cycle around 3:45 a.m., said Senior Cpl. Kevin Janse, a Dallas police spokesman. The Honda motorcycle clipped the center median then ran into a one-way sign.

The driver, who was not wearing a helmet, sustained severe head trauma. He was taken to Presbyterian Hospital in Dallas, where he was pronounced dead at 4:16 a.m.

Cpl. Janse said police were investigating to determine whether excessive speed or alcohol consumption was a factor in the crash.

This was the 99th traffic fatality in Dallas this year.

In the Arlington accident, Dennis Alan Dans, 39, was killed when his 2002 Harley Davidson collided with a 1998 Dodge Ram pickup driven by Ryan Myers, 34, according to Arlington police. They said the collision occurred at the intersection of South Cooper Street and Sublett Road. Mr. Dans was pronounced dead at John Peter Smith Hospital in Fort Worth.