People in Pakistan are mourning the deaths of more than 70 people including 29 children in a suicide attack in a Lahore park, the BBC reports.

The regional government announced three days of mourning, with one day declared in other parts of Pakistan.

Taliban splinter group Jamaat-ul-Ahrar said it carried out the attack and targeted Christians celebrating Easter.

At least 300 people were injured, with officials saying they expected the death toll to rise.

The area was more crowded than usual, as Lahore’s minority Christians had gathered to celebrate Easter at a funfair in the park.

Prime Minister Nawaz Sharif visited some of the injured in hospital and has met security officials to plan a response.

Muslims also died in the attack. At least one funeral was held on Monday.

There were scenes of anguish as parents searched for children amid the debris.

Meanwhile Facebook has apologised after a programme glitch resulted in users around the world being sent a notification to let friends know they were safe after the attack, meant only for subscribers in the Lahore area.

Facebook had been criticised for deploying the Safety Check application more readily if Westerners were the likely victims.

The government of Punjab, of which Lahore is the capital, declared a state of emergency in the city and three days of mourning.

Schools and markets in the province were closed on Monday.

Military spokesman Gen Asim Bajwa tweeted: “We must bring the killers of our innocent brothers, sisters and children to justice and will never allow these savage inhumans to over-run our life and liberty.”

Lahore is one of Pakistan’s most liberal and wealthy cities. It is Mr Sharif’s political powerbase and has seen relatively few terror attacks in recent years.

A spokesman for Jamaat-ul-Ahrar, Ehsanullah Ehsan, said the group wanted to send a message to Mr Sharif that they “have entered Lahore”, and threatened further attacks.

Jamaat-ul-Ahrar is a breakaway group from Tehrik-e Taliban Pakistan. It has carried out several other attacks on Pakistani civilians and security forces in recent months.

The explosion, believed to have been carried out by one suicide bomber, hit the main gate to the Gulshan-e-Iqbal park in the early evening, a short distance from the children’s playground.

Officials said the device had been packed with ball bearings.

Police chief Haider Ashraf said the park had been a soft target for the militants, saying that while Pakistan is “in a warlike situation” there had been no specific alert issued for the park.

Pakistan has suffered regular incidents of Taliban-related violence, sectarian strife and criminal gang activity.