Four people were killed and a fifth was injured in a mass shooting at a Midtown Manhattan office building on Monday.

NEW YORK (Reuters) -Bankers and traders returned to work on a somber Tuesday morning in Midtown Manhattan, New York's financial epicenter, one day after a shooting that killed four people, including a senior Blackstone executive.

Blackstone employees struggled on Tuesday to come to terms with the death of Wesley LePatner, one of the investment firm's senior executives who was gunned down late on Monday as she was leaving her Midtown Manhattan office.