A suspected suicide attack near a mosque in the city of Peshawar in northwestern Pakistan has left dozens of people dead and many more injured, local authorities said on Monday.

Police and hospital officials said at least 59 people had lost their lives and more than 150 were injured in the blast inside a high-security zone next to a police headquarters.

The sensitivity of the location has caused the government to place the country on a heightened state of alert over terrorism.

The bomber detonated his load at the moment hundreds of people were lined up to say prayers, officials said.

Footage from government broadcaster PTV showed police, firefighters and residents working to remove debris from the site and carrying the wounded out on their shoulders. Rescuers brought in heavy machinery to help with the effort.

Meena Gul, a 38-year-old police officer who was at the mosque at the time, said he could hear screams and cries after the bomb was detonated.

Attack succeeded despite heavy security in area

"It was a suicide bombing," Peshawar Police Chief Ijaz Khan said. "We have found traces of explosives."

Prime Minister Shehbaz Sharif condemned the attack calling it "no less than an attack on Pakistan."

"Terrorists want to create fear by targeting those who perform the duty of defending Pakistan," Sharif said.

He made it clear that terrorist attacks "have nothing to do with Islam."

His office also said he would visit the site in Peshawar.

Interior Minister Rana Sanaullah announced an inquiry would soon follow into how it was possible for a suicide bomber to successfully penetrate multiple layers of security.

In a post on Twitter, former Pakistani Prime Minister Imran Khan referred to the incident as a "terrorist suicide attack."

Khan added, "It is imperative we improve our intelligence gathering & properly equip our police forces to combat the growing threat of terrorism."

UN Secretary-General Antonio Guterres condemned the attack.

"It is particularly abhorrent that such an attack occurred at a place of worship. Freedom of religion, freedom of belief and the ability to worship in peace is a fundamental human right," Guterres said.

Taliban deny responsibility for attack

A commander of the Pakistani Taliban, also known as Tehreek-e-Taliban Pakistan, Sarbakaf Mohmand, wrote on Twitter it was responsible for the the blast.

But more than 10 hours later, TTP spokesperson Mohammad Khurasani distanced the group from the bombing, saying it was not its policy to target mosques or other religious sites.

"Tehreek-e-Taliban has nothing to do with this attack," he said in a statement.

Khurasani said those taking part in such acts could face punitive action under TTP's policy.

Peshawar is the capital of the Khyber Pakhtunkhwa province bordering Afghanistan.

Pakistani journalist Yusra Askari told DW that, although "the situation on the border has been relatively calm the last couple of months," the Taliban "recently promised revenge" for several attacks they blame on Islamabad.

lo, es, ar/msh (AFP, Reuters, AP, dpa)