By Mashal Khan 

SWAT, Pakistan — At least 14 people, including police officers, were killed and 20 others injured in a suicide bombing outside a police station during a peace march in Pakistan's northwestern Swat district on Sunday, police and local residents said.

The attack occurred at the main gate of the Kabal police station in Kabal Bazaar, where thousands of people had gathered to participate in a peace march against militant violence in the region.

"The suicide bomber detonated explosives at the main gate of the Kabal police station, where a large number of police personnel were deployed to provide security for the march," local police officer Abdullah told The South Asia Times by telephone.

He said at least 14 people, including police officers, were killed and 20 others wounded.

Rescue 1122 spokesperson Bilal Faizi also confirmed that death toll now raised to 14.

Authorities warned that the death toll could rise as several of the injured remain in critical condition.

The gathering had been organized by local residents to demonstrate against the re-emergence of militants in the Swat Valley, which was once one of Pakistan's most volatile insurgency-hit regions.

Local elder Ahmed Khan said thousands of residents had joined the march to reject the return of militant groups.

"Terrorists have again entered the Swat area and are attempting to derail peace. We want to know who brought these terrorists and how they entered our area from Afghanistan," he said.

Khan said the bombing would not weaken public resolve against militancy.

"The people of Swat will not tolerate the presence of terrorists again. Such attacks cannot force us to stop resisting them. Our people have even taken up arms against these militants, and we will not allow a single terrorist to live in the Swat area," he said.

Swat, often referred to as the "Switzerland of Pakistan" because of its scenic mountains and natural beauty, is one of the country's most popular tourist destinations.

The valley was a stronghold of militants between 2007 and 2014 before Pakistan's military launched large-scale operations that dismantled insurgent networks. The campaign displaced thousands of residents before security was gradually restored.

Following Sunday's bombing, protest rallies were also held in the nearby districts of Dir and other parts of the Malakand division. Demonstrators called on the government and security forces to launch immediate action to eliminate militant groups operating in the region.

No group immediately claimed responsibility for the attack, and authorities have launched an investigation. Emergency services transported the wounded to nearby hospitals as security was tightened across the area.