New York, NY —

A construction worker fell to his death yesterday while installing windows at a luxury condominium high rise under construction on Manhattan's East side.

The city's Department of Buildings says it appears a nylon safety strap that connected the worker to the building failed causing him to fall from the 23rd floor to a 14th floor balcony. Work has been stopped at the site and the Buildings Department is investigating the method used to install the straps.

Commissioner Patricia Lancaster said the toughest enforcement would be pursued. Her agency has been under scrutiny recently after a crane collapsed last month killing seven people. In all 13 people have died at construction sites so far this year. Last year the total number was 12 though in 2006, there were 18 construction related fatalities.