The price, however, was later cut by half, meaning it was still 10 times higher than it should have been.

On Monday night, Jose Angel Matas and Raquel Rviz took the taxi with license plate 51A-311.64 from Ben Thanh market in District 1 to Nguyen Thai Binh market, also in District 1 (a distance of a little over 1 km).

The normal fee for such a short trip would be VND20,000 (US$1), but the driver told them to pay nearly VND400,000 ($20), based on the taxi meter.

This cab’s outside appearance was similar to a Mai Linh taxi, a prestigious taxi brand.

Ms. Jose Angel Matas said she wanted to complain but the driver rumbled on in Vietnamese so she had to cough up the amount he was demanding.

However, in the end the driver returned half the amount to the tourists when they mentioned the police.

The Spanish customers were later given an invoice bearing a Mai Linh logo, but when they took it to the actual Mai Linh Company, they were told the invoice was fake.

They then reported the matter to local police who invited the driver - Mr. Nguyen Thanh Kiet - for a questioning session.

The police also impounded Kiet’s vehicle, which has been registered to deliver taxi services.

Kiet told police the fee was nearly VND40,000 and he received VND200,000, but did not return any change because “I thought it was a tip”.

City traffic inspectors from the Department of Transport are checking whether the taxi meter was rigged.