A Thai F-16 fighter jet bombed targets in Cambodia on Thursday, both sides said, as weeks of tension over a border dispute escalated into clashes that have killed at least two civilians, Reuters reported.

Of the six F-16 fighter jets that Thailand readied to deploy along the disputed border, one of the aircraft fired into Cambodia and destroyed a military target, the Thai army said. Both countries accused each other of starting the clash early on Thursday.

"We have used air power against military targets as planned," Thai army deputy spokesperson Richa Suksuwanon told reporters. Thailand also closed its border with Cambodia, according to Reuters.

Cambodia's defence ministry said the jets dropped two bombs on a road, and that it "strongly condemns the reckless and brutal military aggression of the Kingdom of Thailand against the sovereignty and territorial integrity of Cambodia".