Infant twins were found dead inside a hot car in New York City Friday. According to the New York Police Department, their father forgot they were in the car and went to work — leaving them alone for eight hours.

Juan Rodriguez, 39, worked a full day at a VA hospital in the Bronx about two blocks away before returning to his Honda sedan to find the 1-year-old boy and girl, NYPD officials said in a news release. He was gone from 8 a.m. to 4 p.m. and police believe he accidentally left the twins in the car.

When Rodriguez returned to the car, he found the infants motionless in the back seat, officials said. A bystander called 911, and the infants were pronounced dead at the scene.

Get Breaking News Delivered to Your Inbox

"He was going crazy. He didn't know what he's gonna do," witness Enis Kricic told CBS New York.

Rodriguez faces two manslaughter charges and two counts of criminally negligent homicide for the deaths of Mariza and Phoenix Rodriguez.

"The vehicle had tinted windows, so it was almost impossible for anybody to notice that the children were there," NYC Councilmember Fernando Cabrera said.

Temperatures were over 85 degrees Fahrenheit in New York City on Friday. The Medical Examiner's office will determine the cause of death, which is believed to be heat exhaustion. The investigation is ongoing.