At least 13 people have been killed and 20 others wounded in an explosion targeting a cinema in Pakistan's northwestern city of Peshawar, Al Jazeera's correspondents have said.

Tuesday's blast hit Shama cinema, known to show adult rated movies, and is owned by the Bilour family, one of the most powerful political families in Khyber Pakhtunkhwa province, said our reporters.

City police chief Mohammad Ijaz Ahmed said three grenades were used and up to 80 people were in the cinema at the time.

The attack came as negotiators for the Pakistani government and for Taliban fighters met for a second time as part of efforts to end the seven-year conflict.

The main Tehreek-e-Taliban Pakistan (TTP) armed group, whose representatives are in talks with the government, denied responsibility for that attack.

Al Jazeera's Kamal Hyder reported that there is a feeling in the country that a third force is trying to sabotage talks between the government and the Pakistani Taliban.

Second attack in 10 days

Bashir Bilour, a former senior minister in the province, was killed in 2012 in a suicide attack. Shama had continued to operate as a result of the Bilour’s political links despite threats in the past.

Reports said there was a specific threat against the cinema in the past few weeks, leading to increased security, but staff had only just returned to "normal" security levels when this attack occurred.

The blast is the second attack in a matter of days.

In the same city on Monday, a suicide bomber's explosive vest went off in the house of a pro-government tribal elder, killing four women, police said.

It was not clear if the attacker set the vest off deliberately. He had run into the home of the elder, Jan Mohammad Afridi, in the city's Chamkani area, after local residents found him suspicious and the police started chasing him, said police chief Ahsan Shah.

Peshawar is the capital of Khyber Pakhtunkhwa province, which lies next to tribal areas that are bases for several networks including the Pakistani Taliban.

It was not known if Afridi, who was in the opposite part of the house at the time, was the initial target. Shah said police surrounded the house and exchanged gunfire with the bomber.

At some point, his explosives were detonated although it was unclear whether the assailant blew himself up or if one of the bullets from the gunfire set off the explosives.

Shah said half of Afridi's house was completely destroyed in the blast and that four bodies of women were recovered from the rubble.

He said five others in the house, including a woman and two children, were wounded. Afridi is a prominent member of the local "peace committee,'' a group that opposes militants in the area.

PHOTO CAPTION

Pakistani volunteers search a cinema hall after a grenade attack in Peshawar on February 11, 2014.

Aljazeera