The woman was walking along a sidewalk in the city's central Westend district when the 11-metre high tree fell, taking her down with it. Bypassers were able to pull the woman from beneath the tree before rescue workers arrived, but she died later at a local hospital, police said.
The tree also took down a lamppost and damaged a gas line as it fell. Fire department workers plugged the leak and closed the street for clean up. Police also reported that an eyewitness suffered from shock.
Authorities are unclear what caused the tree to fall. It was on a piece of private land and not known to be rotten, the fire department said. There was also no wind when the tree broke from its trunk, a city spokesperson said.
Criminal police are investigating the incident.