The blast at Lahore's Gulshan-e-Iqbal Park seemed like a suicide bombing but investigations are ongoing

A blast ripped apart a public park in Pakistan's eastern city of Lahore, the capital of Prime Minister Nawaz Sharif's political heartland of Punjab, rescue officials said.

The deafening explosion — apparently caused by a suicide bomber — hit gate no.1 around 6:30 pm when the park was teeming with families, specially women and children, dazed witnesses said.

"At least 10 people have been killed in a blast outside Gulshan-e-Iqbal Park," Jam Sajjad Hussain, spokesman for Rescue 112 said, adding that more than 30 people were injured and had been taken to various hospitals in the city. Most of the injured are women and children, Hussain said.

Senior police officer Haider Ashraf said the explosion took place Sunday in the parking area of Gulshan-e-Iqbal park. He says the explosion appeared to have been a suicide bombing, but investigations were ongoing.

He says the area was crowded because Christians are celebrating the Easter holiday and many families were leaving the park when the blast occurred. He says the death toll could still rise as many of the wounded were in a critical condition. In fact, Pakistani newspaper Dawn tweeted that the death toll was at least 53. Emergency has been declared at all government hospitals in Lahore, the paper said.

Latest update: At least 53 dead after explosion in Lahore's Gulshan-i-Iqbal Park https://t.co/yRB5BWi9T8 pic.twitter.com/JGCmku0qld — Dawn.com (@dawn_com) March 27, 2016

ARY News said five to six kg of explosives may have been used in the explosion, which was heard in a large part of Lahore, capital of Punjab province.

Some reports said the bomb might have been fixed on a parked motorbike.

Xinhua said the injured were shifted to Sheikh Zaid hospital where several of them were said to be in critical condition.

Pakistan, a nuclear-armed nation of 190 million people, is plagued by a Taliban insurgency, criminal gangs and sectarian violence. Punjab is its biggest and wealthiest province.

With inputs from agencies