CHICAGO (CBS) — A woman was robbed at gunpoint and sexually assaulted outside her home in Chicago’s West Town neighborhood.

It happened last Tuesday in the 2000 block of West Ferdinand Street. The woman noticed a man riding a blue bicycle, possibly a Divvy bike, in the street.

The woman says she rushed inside her home, but went back outside after noticing the man in her yard.

Police say the man showed a gun, demanded cash, and sexually assaulted the woman.

Police are warning people in the West Town community to be on heightened alert.