Man on handicapped electric motor wheel chair

After work I went home. Took a shower and went to visit my mother. I left her home after the visit. The time was14.45. I had to walk down the stairs to the main road, ANG mio kio Avenue 8. The Mrt station is two bus stops from my mother's home. I have to cross a road leading to Avenue 8. When I reached the road junction I saw a man on motorised wheels chair. He saw me and he tried to hid himself, I mean to hid his head behind the MRT track pillar. I stopped at the junction, he was still visible. I took my eyes away from him and concentrated on the road to check to make sure there was no vehicles. I crossed the road, upon reaching the other side where the motorised wheel chair was. The motorised wheel chair and the man vanished. I looked everywhere for him, he cannot travel very far in a short time. I could not see him.