MIAMI -- A man jumped to his death from the downtown Miami Center building on Monday, police said.

Police said Guillermo Martinez jumped from a Citibank Group office on the 29th floor of the skyscraper.

Police said that Martinez, 40, was a temporary clerk in an investment firm in the building. According to police, Martinez locked himself in his boss' office with a sledgehammer that he used to break the glass window and threw everything on her desk out of the window, including her computer terminal and chair, before he jumped.

Martinez died on impact.

Unconfirmed reports were that he was not doing well at work and thought he was about to get fired, police said.

The building is located at 201 S. Biscayne Blvd.

Biscayne Boulevard northbound was shut down during the investigation.