Twin infants died after their parents unintentionally left them in a hot car in an apartment complex parking lot, investigators said.

Paramedics were called to The Maisonette Apartments around 2:29 p.m. Thursday for two infants in a vehicle in cardiac arrest, according to the Richmond Times-Dispatch.

"It wasn't intentional," Chesterfield police Maj. Frank Carpenter told the Times-Dispatch. "We believe it was truly an accident."

The 5-month-old boy and girl were taken to the hospital where one was pronounced dead soon after arrival. The other child died several hours later, according to the Times-Dispatch.

Because it’s an ongoing investigation, authorities on Friday could not reveal the circumstances regarding the children being left in the vehicle or for how long inside they were left alone.