A woman has died after she collided with a CTA bus while on a motorcycle in Ashburn early Sunday, police said.

The woman, 41, was alone on a three-wheel motorcycle in the 7800 block of South Western Avenue around 4:15 a.m. when the crash happened, according to Chicago police.

She was taken to Advocate Christ Medical Center, where she was pronounced dead.

It’s unclear if the woman was wearing a helmet.

No other injuries were reported, and the Chicago Police Department’s major accidents unit is investigating the crash.