Name of early 90’s cop show?

I saw this TV show in Poland in the early 1990’s, it was either channel 1 or 2, free-to-air TV. I think it aired on Thursday night and the repeat was shown during the day on Friday.

I remember one of the episodes had a guy on a boat who had his hand-gun jam, and he ended up getting shot because of it, the scene took place in the day time. This could have been episode 3 of the season.

The next episode had a couple get murdered in an underground car park, at night time, by a guy with a ponytail (he looked like Data from TNG, but he had a ponytail). There was also a close up shot of a bloody hand on the car park ground after the couple gets murdered. I remember a scene where the ponytail bad guy was getting interrogated at a cop-station later in the episode. The bad guy also used a 9mm Beretta 92F (from memory, it could have been a different 9mm gun).

The next episode had a bad guy assassinating someone with a silencer hand gun, whilst driving in his car, in a park, in the daytime.

 The show could have ended after only 5 episodes. Many help for any help with this.