The incident took place at around 10 pm yesterday night when Kynpham N Syiem (40) along with four other friends were returning from work, they said.
The attackers stopped Syiem at Dangar village in East Khasi Hills District and attacked him with sharp weapon leaving him critically injured, SP City S Thamar said.
The accused identified as Kyllangshngain Thongni and Pustirwel Disiar are absconding after the incident, he said.
Kynpham has been admitted in Woodland Hospital.
Pynshngain Syiem is the chief executive member of the Khasi Hills Autonomous District Council and was elected Mawsynram MLA twice.