The death toll in Sunday night's van-truck collision on the Unnao-Hardoi highway has gone up to seven.
It was initially said that three persons were travelling in the van when it caught fire following a collision with a truck.
However, when the fire was completely doused and the van doors were cut open, seven skeletons were found inside.
The bodies had been charred beyond recognition.
Unnao Superintendent of Police Vikrant Veer Singh said that preliminary investigations have shown that the accident took place when one of the tyres of the speeding car burst, the vehicle veered to the left and caught fire after hitting a truck in another lane. The CNG kit installed in the van caught fire.
Sources said that the seven deceased, including the driver, were on their way to attend a marriage.
They have been identified as Shambhu, Himanshu, Amit Mishra, Kallu, Khajan Singh, Ankit and Bal Krishna.
"We will use DNA sampling to identify the bodies which have been completely charred," the SP said.
Taking note of the incident, chief minister Yogi Adityanath has directed the district administration to provide all possible help to the victims' family.