Updated

An anti-corruption investigator blinded by an acid attack is urging graft fighters to "stay brave" as he returns to Indonesia after months of medical treatment.

Activists said they would dress in white to greet Novel Baswedan when he arrives Thursday at the Corruption Eradication Commission in Jakarta.

Baswedan was leading a probe into a scandal that has implicated high-profile Indonesian politicians when he was attacked in April last year as he left dawn prayers.

Baswedan said in a video posted online: "Let's stay focused, stay brave. Don't be afraid, don't hesitate, stay strong."

He said his right eye is now "quite stable" but still cannot see from his left eye.