Fourteen children died after the roof of a building near Lahore collapsed on top of them, officials say.
The incident happened at a private tuition centre in the Kahna suburb of the Pakistani city.
Young children under the age of 10 are among those to have been taken from the scene.
Authorities launched an investigation into the collapse, and two people were taken into custody as part of the initial inquiry.
Farooq Ahmed, a spokesman for the emergency service Rescue 1122, told the BBC they had received a call about the incident at 16:45 (12:45 BST).
He said that the rescue operation had been completed within one hour, and most people recovered were between seven and 11 years old.
Another five people are thought to be injured.
A man who said his niece was among the victims told AFP the roof of the building had been "in poor shape".
Zaheer, 45, told the news agency that tiles on the roof had been undergoing repairs while the children studied.
"Suddenly the roof collapsed on top of quite a few children," he said.
"They put a lot of weight on the roof and that's why this has happened."
Another resident told the Associated Press: "We don't know whose home to visit first to offer condolences for the loss of their children."
Pakistan's prime minister expressed his condolences following the incident in a statement reported by AFP.
In the message, attributed to his office, Shehbaz Sharif said he "prayed for the speedy recovery of the injured and directed the authorities to provide them with every possible medical assistance".
The chief minister of Punjab, Maryam Nawaz Sharif, called it a "heartbreaking tragedy".
In a message shared on X in English, she said that "the loss of 14 innocent lives is an immeasurable sorrow, and my heart goes out to the grieving families".
"Every individual found accountable will face the full force of the law," she added.
