Three people have been arrested and two air pistols seized in connection with a case in which a mainland man was wounded in a fight on a busy Hong Kong street last week.On Monday, officers were still on the hunt for a suspected triad member behind the attack on the mainlander, 33, over a money dispute. The weapon used in the incident was believed to be a construction tool.“No bullet head or cartridge was found in the incident, but metal fragments were lodged in the victim’s wound,” one law…