A Citigroup Inc. executive was found dead his Manhattan home on Tuesday. Police said his death was caused by a slash to his neck, according to The Wall Street Journal.

Emergency responders reached 42-year-old Shawn Miller at 3 p.m. on Tuesday in his apartment in New York's Financial District. Miller had marks on his arms and throat. He was pronounced dead at the scene according to The Wall Street Journal.

Police are calling the death suspicious and the autopsy performed on Wednesday was inconclusive, a spokesperson said, according to The Wall Street Journal.

Miller joined Citigroup Inc. in 2004. He was managing director of environment and social risk. Miller "was highly regarded at Citi and across the financial services industry as a thought leader and tireless advocate for environmental and sustainable business practices," Citigroup said in an employee memo, according to The Wall Street Journal.

Police are looking for a man who was in the 120 Greenwich St. building's elevator with Miller around 6:30 p.m. on Saturday. The man left the next day at 4:45 p.m., but returned 15 minutes later. Miller told the doorman at that time that the man was "not welcome in the building" and the man was turned away, according to The Wall Street Journal.

The last time surveillance video caught Miller alive was at 6:30 p.m. on Monday. A man who identified himself as Miller's boyfriend called the doorman on Tuesday about 2:30 p.m. saying he couldn't get in touch with Miller and he was concerned. That's when the doorman found the unconscious Miller in his bathtub, according to The Wall Street Journal.