Twelve children were among the 13 killed when a truck collided with their school bus on the Jalandhar-Nakodar road on Monday morning.
The condition of three children is serious.
The children were on their way to school when the mishap occurred near Jaheera village in Lambhra, close to Nakodar, Jalandhar Range's Inspector General of Police Gurpreet Deo said.
The driver of the school mini bus, which was carrying 24 students, all in the age group of 8-10 years, was also killed in the mishap, she said.
A case of rash and negligent driving was registered against the truck driver, who fled after the accident.
"The mishap took place at 8 am in Jaheera village when the bus of Akal Academy was taking students to the school," Jalandhar Rural Superintendent of Police Rajinder Singh said.
While seven succumbed at the accident spot, others died on way to the hospital. Three students are serious and have been admitted in a hospital, while others are out of danger, he said.
The area where the mishap occurred is said to be prone to accidents.
The impact of the accident was so bad that the roof of the school mini bus was torn off and the vehicle was virtually reduced to a heap of metal. School bags, tiffin boxes and colourful pencil boxes lay strewn at the site.
Most of the victims belonged to nearby villages. The bodies were taken to the Nakodar hospital and later handed over to their parents.
Punjab Deputy Chief Minister Sukhbir Singh Badal expressed grief over the loss of lives and directed the district authorities to provide immediate medical aid to the injured.
Jalandhar Deputy Commissioner Shruti Singh announced a compensation of Rs 1 lakh to the next of kin of those who died and free medical aid to the injured.