This happened on Tuesday evening this week. I couldn’t find any English language news articles, but many Finnish newspapers have reported it, including comments from Mika Salo himself. Here is a link to one Finnish article with his comments, as well as images of the wound:

https://www.is.fi/formula1/art-2000012025708.html

Here are a few translated excerpts from the article:

"former Formula One star Mika Salo, 59, was stabbed in Bangkok, Thailand, on Tuesday evening. At least that's what the doctor who treated Salo suspected after seeing a deep open wound on the side of the Finn's calf."

"The events began when Salo was at the traffic lights near his hotel. He started walking across the pedestrian crossing.

– There are an incredible number of those mopeds here, they pass by on that. One came quite close and I felt that I hit it a little. But not that it even hurt. I continued walking normally and then 5–10 meters away a man behind me said, hey, your foot is bleeding a lot. I looked down and saw that my shoe was completely covered in blood."

"– I thought, oh my God, that wound is big. It won't heal with a band-aid.

A taxi took Salo to a nearby hospital, where the wound was stitched up right away. The wound was deep but clean. The doctor estimated that the calf had been cut with a knife.

– He looked at it and said that it had been pulled with a really sharp object. He suspected a knife. Of course, that's not certain, but the wound was so clean and straight.

– Then when I went to the hospital the next day to clean it, they told me that there had been several similar cuts that evening and night."

“I have to praise the doctors and hospitals here. They are incredibly good, and everything goes smoothly without any waiting at all. No complaints whatsoever.”

Salo has not started to feel afraid of moped riders when moving around the city.

“In a big city there are always idiots mixed in. Luckily this hit my leg and not somewhere else. It seems like someone only tried to cause harm, if this was intentional. If they had wanted to do more damage, they would of course have aimed at the upper body. Then I might not be talking much about this now.”

Unfortunately, the article doesn’t mention exactly where this happened.

I've seen back footpegs where the outer edge becomes quite sharp. If they were down with no back rider I can see the slash coming from there.

I have a hard time believing someone is riding around with a knife sticking out at calf level.

14 hours ago, Priorexpat said:

I've seen back footpegs where the outer edge becomes quite sharp. If they were down with no back rider I can see the slash coming from there.

I have a hard time believing someone is riding around with a knife sticking out at calf level.

I suppose it’s possible, but if you look at the photo in the article, it definitely looks like more than just a scratch from a footpeg:

15 hours ago, Priorexpat said:

If they were down with no back rider

Isn't the rear foot pegs down with no passenger illegal. One of those weird Thai traffic laws.

8 hours ago, VocalNeal said:

Isn't the rear foot pegs down with no passenger illegal. One of those weird Thai traffic laws.

If so that is a good law.

@Antti you're right, I would expect what I was thinking it would be a more horizontal cut. Thats a nasty wound for sure.

Thank god his entry fee coveted the mandatory visitor health insurance. Phew

Was he wearing a gold chain?

This is now in the news section, please continue there.