"An FBI agent approached me and identified himself and asked me if I recognized the gentleman and asked me if I've seen him," said resident Melissa Matthews.
Neighbors are now shocked to learn the man accused of killing at least eight people in Lower Manhattan may have lived next door.
"We never feared anything because he had a family too," said Matthews. "He was there with his wife and children. The children were young ... he had a whole family as well. So, no one ever suspected anything."
We've also learned that Saipov's Florida ties may stretch beyond Tampa.
WFTX-TV in Fort Myers uncovered several addresses listed under the suspect's name.
In Tampa, investigators would not comment on their search but did spend much of their time inside one apartment.
"That really upset me when I heard the news," said neighbor Mohamed Soliman. "I couldn't believe that somebody be very close and live, used to live in the same apartment."
Law enforcement officials have confirmed that Saipov spent the last few months in Paterson, N.J., living with family.