Police have released the name of the woman and baby who died following a fiery crash in the Waikato.

Two-month-old Soriah Harper and 39-year-old Amanda Saunders, of Silverdale, Hamilton, died when they were involved in a three-car crash in Eureka on Tuesdy afternoon.

A man who was first on the scene says what he saw will stick with him for the rest of his life.

The man who lives nearby rushed out to find a man, woman, and baby in a black vehicle, which was most damaged in the crash.

People from two other cars had already escaped, said the man, who spoke to Stuff on the basis of anonymity.

The driver door had been ripped off in the crash.

The man told Stuff he reached into the back seat to check for the baby's pulse, but it was too late.

Everyone who was able to get out of their vehicle safely had, and all he could do was wait for emergency services. Read more here.

In a statement confirming the identities of those killed in the crash, police say they would like to extend condolences to their whānau and friends at this difficult time.

An investigation into the crash is ongoing.