Islamabad: Two policemen and a polio worker were killed in an attack in Pakistan's Khyber Pakhtunkhwa province on Tuesday, media reports citing police sources reported.

A polio team escorted by police was administering polio vaccines to kids in the North Waziristan district when the incident occurred, Xinhua News Agency reported.

"Unknown gunmen opened fire at the polio team and fled the scene. A kid who was receiving drops also got injured in the attack," the sources said.

In a separate incident in Punjab province, at least five persons were killed after they inhaled poisonous gas inside a well in Rawalpindi city.

As per local media, a man went inside the well in the Rawat area to clean it but fell unconscious due to the accumulation of poisonous gas.

To evacuate the fainted person, seven people immediately went inside the well but they also fell unconscious, Xinhua reported citing sources.

After receiving the information, police and rescue workers rushed to the site and started a rescue operation, said the reports.

Five people died due to suffocation while three people were rescued alive and were shifted to a hospital, reported Xinhua.

Meanwhile, tension gripped Khyber Pakhtunkhwa's Kurram district after unidentified people killed a man and left another injured, making it the second incident of the targeted killing in a month in the district.

The incident took place near Sadda town of Kurram tribal district last Tuesday, Dawn newspaper reported.

The victims were heading from Parachinar to Peshawar. Mobile phone service and internet were suspended in the district after the attack.

This was the second incident of targeted killing in Kurram. Earlier on June 15, a car was attacked in Topaki village in the district's lower subdivision. The chairman of the local peace council, Momin Khan, along with two others was killed while another person was injured.

After killing of the chairman, a video went viral on social media in which sacrilegious remarks were made.

Meanwhile, General Officer Commanding Major General Aqib Iqbal held meetings with elders in Parachinar on Monday and discussed the prevailing situation, Dawn reported.