Detectives have commenced an investigation into an armed robbery at a service station in East Toowoomba early this morning.

Around 4.40am a man entered the Cohoe Street business before rushing to the counter armed with an unknown round object and demanding money from the attendant.

The male employee complied with his demands and handed over a sum of cash.

The man then fled the scene on foot and was last seen heading towards Tourist Road.

No one was physically injured during the incident.

The man is described as being about 170cm tall with a medium build and was wearing a black jumper, dark long pants and had material covering his face.