At least 33 people were killed and over 40 were injured on Monday when a passenger bus collided with a truck on the Indus Highway in Dera Ghazi Khan, Punjab, officials said.

The bus was travelling from Sialkot to Rajanpur.

Initially, Commissioner Dera Ghazi Khan Dr Irshad Ahmed confirmed that 29 people, including women and children, had died in the incident. He said rescue officials reached the site soon after the accident, adding that dead bodies and the injured were being transferred to the DHQ Teaching Hospital DG Khan.

Later, DHQ Teaching Hospital Medical College principal Dr Asif Qureshi told Dawn.com that the death toll from the accident had risen to 33.

According to the hospital management, four of the 41 injured were in a critical condition.

Prime Minister Imran Khan said he was "shocked & deeply saddened to learn of the tragic road accident of a Rajanpur bound bus, near DG Khan resulting in the loss of 30 precious lives". He added that he had directed the Punjab government to offer swift support to the victims' families.

Interior Minister Sheikh Rashid expressed his sorrow over the deaths in the accident. He said the incident was nothing less than a "calamity" for people going back home for the upcoming Eidul Azha holidays.

"May God raise the dead to a higher level in Paradise [and] give the family the courage to bear the trauma," he tweeted.

Federal Information and Broadcasting Minister Fawad Chaudhry tweeted: "When will we as a nation realise that violation of traffic rules is fatal? Public transport drivers are the trustees of people's lives [and] they need to take further precaution."

Meanwhile, Special Assistant to the Punjab Chief Minister Dr Firdous Ashiq Awan said the incident was very "sad and tragic".

"The heart is aggrieved at the loss of precious lives in the accident. The Punjab government shares in the grief and pain of the victims' families in this hour of grief," she tweeted.

She said that an emergency had been imposed in the hospitals and the injured were being provided with the "best medical treatment facilities", with Punjab Chief Minister Usman Buzdar himself supervising all matters.

"Report of the incident has been sought. The perpetrators of negligence in the accident will be brought to justice," she added.

Chief Minister Buzdar also expressed grief over the loss of lives in the accident and extended condolences to the bereaved families.

He said in a message on Twitter that the injured were being provided the best medical treatment and strict action would be taken against persons due to whose negligence the accident had taken place.

Opposition Leader in the National Assembly and PML-N President Shehbaz Sharif tweeted: "Deeply pained & heart-broken at the tragic loss of precious lives in a road accident in DG Khan. Can't imagine the anguish the affected families should be going through. May Allah give them Sabr! They are in our thoughts & prayers. Inna Lillah e Wainna Elahi Rajioon!"