Calgary police are investigating after an elderly pedestrian was hit in a marked crosswalk in the city's southeast.

A 72-year-old man was hit by a 2007 Chevrolet panel van last Wednesday morning at the corner of 44th Street and 17th Avenue.

He was taken to hospital in serious condition, but his health has deteriorated since then.

The driver of the van was not injured.

Anyone who witnessed the crash or events leading up to it should contact the Calgary police traffic unit or Crime Stoppers.