At least three soldiers were killed and two others injured in a cross-border attack from Afghanistan's Kunar province into Pakistani tribal area of Bajaur Agency in the wee hours of Saturday morning, local media reported.
Samaa TV said that an unknown number of gunmen coming from Afghanistan opened fire at a security check post located in Mamoond town of Bajaur Agency, a volatile tribal area near the Pakistan-Afghanistan border.
The attack left three troops including a captain killed and two others including a soldier and a civilian injured.
Some media reports claimed that the forces killed five militants in retaliatory attack.
Officials did not confirm the report yet.
The injured civilians have been shifted to a nearby hospital.
Saturday morning's incident is the fourth cross-border attack in the area over the last two months.
Earlier in two attacks in May, at least one soldier was killed and six others were wounded when militants coming from Afghanistan attacked Pakistani check posts in Bajaur Agency.
On June 4, four soldiers were killed and three others sustained injuries in a similar attack in the area.
Nineteen militants were also killed in retaliatory attack by Pakistani forces.