At least four people, including two activists of the Pashtun Tahafuz Movement (PTM), were killed and dozens of others injured in a militant attack in South Waziristan agency's headquarters of Wana on Sunday, sources said.

Sources told DawnNewsTV that the militants targeted a PTM rally that was organised to welcome one of the movement’s leaders, Ali Wazir.

PTM leader Mohsin Dawar confirmed the incident, saying the militants opened indiscriminate fire at the rally, killing and injuring a number of PTM supporters.

While quoting reports received from Wana so far, he said four PTM supporters have been killed and dozens injured in the incident.

“Our workers are busy in shifting the injured to the hospital,” Dawar said, adding that they are trying to obtain more information.

A local source told DawnNewsTV that two PTM workers and as many local residents were killed in the firing incident. He added that the number of deaths may rise as several of the injured are in a critical condition. The numbers could not be immediately verified by officials.

According to AFP, supporters of PTM, which is led by young activist Manzoor Pashteen, wanted to hold a rally to protest against growing corruption in the tribal regions.

“The clash erupted after supporters of Manzoor Pashteen were stopped from holding a protest rally by local militants belonging to Maulvi Nazir group,” a senior local administration official told AFP on condition of anonymity.

The Pashtun activists torched two offices of the militants, which led to an exchange of fire, killing two people and wounding 25 others, the official said.

The local administration immediately imposed a curfew on the area to control the fast deteriorating situation, a local intelligence official, who confirmed the incident and casualties, told AFP.

Another official said efforts were underway to bring the situation under control, adding the local administration was holding talks with the “two parties”.

PTM rose to prominence earlier this year after the killing of a young social media star, Waziristan native Naqeebullah Mehsud, in Karachi unleashed festering anger at extrajudicial murders.

An organisation working for the rights of those affected by the war on terror in tribal areas especially those from South Waziristan, PTM has staged protests in different parts of the country against alleged enforced disappearances, extrajudicial arrests and killings, as well as the alleged mistreatment of the Pakhtun community by security forces.