A Wellington Metlink bus driver is under fire after allegedly ignoring a vulnerable elderly man waiting at a bus stop for a ride home.

On Tuesday night at 8.31pm a "disorientated" elderly man was waiting at the Karori Park bus stop sign to be taken home.

However, the bus driver stopped in the middle of the road to let off a passenger before allegedly ignoring the elderly man and driving off, leaving him stranded.

Bystander Yu Ruan happened to capture the incident on his dashcam, with the Wellington resident telling the Herald the man appeared to be vulnerable, "disorientated" by the incident, and appeared lost.

Ruan offered to drive the man home, but his response left the good Samaritan alarmed for the elderly man's wellbeing.

"After dropping off a passenger I thought the driver was going to creep forward to where the bus stop is where the man was waiting.

"Then the bus just drove off. I thought, damn, that's not good. The elderly man looked pretty sad and he started walking in the direction of where the bus came from.

"I went up to him and said 'hey man are you heading home?' I asked him how far away he was travelling and he said just a few blocks. I told him I'd drive him close to his home."

As Ruan drove closer to where the man said he was staying, he worked out his passenger suffered from a form of memory loss condition and grew increasingly worried about his safety.

"I asked him for his address so I could drop him home but he explained it was difficult to describe before becoming disorientated.

"He said 'my house is close', so I dropped him up the road. He started wandering around and appeared to forget where he was going. I was pretty worried for his wellbeing and safety."

Ruan said his conversation with the man uncovered he regularly takes public transport to get around town, and he believes the man was thrown off by the bus driver ignoring him at the bus stop.

The Wellington resident dropped him off at St Albans before calling police, asking to check up on the man.

He says the bus driver should have never ignored the waiting passenger, and is glad the situation didn't take a turn for worse.

"He seemed lost. I think he has Alzheimer's. I did a U-turn to try find him. I called police and explained I dropped him off near his home but I'm worried for his safety so I asked them to double check on him.

"After posting on social media I received a few messages saying the man was knocking on doors near his home. Police then called me back to let me know they were checking up on him.

"Luckily he made it home safe but I believe he's a regular user of the bus.

"To not be picked up must have been alarming for him. Last night was bad. It was dark. The driver shouldn't have left the elderly passenger there. Especially since he was waiting in the right place."

A Greater Wellington Regional Council spokesperson told the Herald the company are aware of the incident although are scarce on details but have apologised for the elderly man's experience.

"After watching the video this looks like an awful experience for the gentleman," they said.

"This is an unfortunate and so far unexplained incident which we will look into. We are glad that he made it home safe and well, but are sorry it happened."

The regional council spokesperson told the Herald bus drivers should safely drop off and pick up customers at designated bus stops, but explained there are occasions where drivers cannot get into the parking area.

Locals have since taken to social media to voice their frustration at Metlink, with many saying they're often ignored in broad daylight.

"I've had buses completely ignore me and others in broad daylight in Karori in recent months too. I'm sick of myself and others having to make this same complaint over and over about buses driving off and leaving people who wanted to get on behind," one person said.

Others commented on the elderly man's experience, saying they're disappointed in the driver.

"It's not even the fact the driver drove off that's making me disappointed in the system, the driver couldn't even be stuffed to actually pull into the park properly to let that person off. How sad can somebody be?" one person wrote.

Another said: "Good on your for picking the man up and taking him home. I'm angry at the driver, makes me think the driver saw the guy and deliberately stopped further away. Seriously, why else stop so far out and back?"

Greater Wellington Regional Council said they will contact the driver.