Islamabad, Jan 16 (IANS): At least four people were killed and 25 injured in a blast inside a tableeghi markaz (preaching centre) in Pakistan's northwest Peshawar city Thursday evening, local media reported.

Quoting the superintendent of police, local Urdu TV channel ARY reported that the blast occurred on the first floor of the building when over 100 people were offering evening prayers.

The incident happened in the city's biggest such centre located in the densely populated Charsadda Road area of Peshawar, the capital of the country's northwest Khyber Pakhtunkhwa province, Xinhua reported citing ARY.

The injured have been shifted to various hospitals in the city, including Lady Reading Hospital, where emergency has been declared.

The media is not being allowed inside the hospitals due to which the condition of the injured people is not known yet.

Rescue teams said that the casualty figure might rise as more people were being brought to the hospital.

Neither has the nature of the blast been determined nor has any group claimed responsibility for the attack yet.

Police have cordoned off the area and launched a search operation.