Authorities have closed a key road outside a major population center in northwestern Pakistan after residents threatened to take their protest over the violent deaths of four teens to Islamabad.

Angry locals from the rural town of Jani Khel are in negotiations with local authorities to demand greater security guarantees and a thorough and credible investigation into the killings, which are at the center of a weeklong sit-in protest.

The residents said on March 26 that security forces placed heavy shipping containers on a local bridge, closing it to traffic.

The bridge links Jani Khel to the nearby city of Bannu, a major population center in the province of Khyber Pakhtunkhwa.

A lawmaker from a nearby area accused state authorities of blocking the road to keep the protest from spreading.

“Instead of listening to the demands of the protesters, the state has chosen to block roads around the area to stop them from moving out if they choose to take their protest to Islamabad,” lawmaker Mohsin Dawar, who represents North Waziristan, which borders Jani Khel, tweeted on March 26.

Many of those same residents began the sit-in on March 21 after the bullet-riddled corpses of four teenagers were discovered in a field some three weeks after they disappeared while hunting birds.

The bodies of the youngsters -- where were between 13 and 17 years old -- were reportedly dug out of the field after a shepherd's dogs found them.

The protesters' primary demand is a government guarantee that Taliban and other militants won't be allowed to operate in the area.

The protesters also want an official complaint filed against a specific security official posted to the town.

Police have already announced a murder investigation.

Mahmood Khan, the chief minister, the most senior elected official in Khyber Pakhtunkhwa, assured protesters on March 25 that the government will investigate.

“I want to promise you that we will hunt those criminals responsible for this heinous act,” he tweeted on March 25.

Authorities have also agreed to pay compensation to the families of the slain teens.