A drone attack on a police headquarters in a major border town in eastern Myanmar has killed at least five officials including a senior army officer and a district administrator, members of two emergency rescue teams and media reports say.

The attack, carried out on Sunday evening in two stages, is believed to be the deadliest aerial bombing targeting high-ranking security and administrative officials since armed resistance was launched more than two years ago against the military that seized power in February 2021 from the elected government of Aung San Suu Kyi.

The takeover was met with peaceful protests but, after security forces cracked down with lethal force, many local armed resistance groups were formed and loosely organised into what is called the “People’s Defence Force” or PDF.

It is the armed wing of Myanmar’s shadow “National Unity Government,” which views itself as a country’s legitimate administrative body.

The PDF has allied themselves with major ethnic guerrilla groups in border regions that have been carrying out armed struggle against the army for decades, seeking greater autonomy.

Lieutenant Colonel Aung Kyaw Min, the temporary commander of a battalion based in Myawaddy township, and ​a traffic police officer died in the attack, said two rescue workers speaking on condition of anonymity because they feared arrest for disclosing the information.

Myawaddy District Administrator Soe Tint, his aide-de-camp Tun Tun Nyein and a clerk died on the spot when drones dropped two bombs while they were inspecting the damage caused by a drone attack about an hour earlier, they said.

The district police office compound is located in downtown Myawaddy, a key trading centre in south-eastern Kayin state on the border with Thailand.

They added that 10 security and administrative officials were being treated in township and military hospitals in Myawaddy while four others including the head of the district police office were sent to a private hospital in Mae Sot, a city in neighbouring Thailand, which has better medical facilities.

Independent online Myanmar media that operate underground, including The Irrawaddy and Khit Thit media, reported the attacks were carried out by Federal Wings, a resistance group that conducts drone warfare in co-operation with the PDF and its allies belonging to ethnic Karen armed groups.

The military information office, the Tatmadaw True News Information Team, said in a statement that some members of security forces and civil servants were injured after the Karen National Liberation Army and the PDF dropped two bombs from a drone.

Drones have become crucial for the resistance forces, which are outmanned and outgunned by the military that has carried out air-strikes unimpaired.

Initially, smaller drones with lighter payloads were used but now the opposition groups are using more sophisticated systems to drop explosives precisely on the military targets.