Video footage shared on social media showed men mimicking planes at St Mary's and the Saints confirmed authorities had taken the details of two individuals.
An initial search and rescue effort was called off by Guernsey Police after three days on January 24.
The plane was located on the seabed off Guernsey on Sunday using a remotely operated vehicle, during which time a body was found amid what remained of the light aircraft.
A recovery operation was then launched following consultation with the families of Sala and Ibbotson, and the police.
The football world came together in grief and to pay its respects as the severity of the Sala story began to unfold, with floral tributes laid outside Cardiff City Stadium and vigils held in Nantes, where 42 goals in three-and-a-half seasons made him a fan favourite.
Southampton asserted their intention to ban anybody found to be involved in taunting the travelling Cardiff fans.
A statement from the club read: "Southampton Football Club can confirm that two fans were detained and had their details taken by police during our match against Cardiff City on Saturday.
"The club will continue to work with Hampshire Police to identify any individuals deemed to have made indecent gestures towards Cardiff supporters.
"Such behaviour has no place in our game and will not be tolerated at St Mary's. The club will be taking an extremely firm stance against anyone involved and intends to ban those supporters identified."
Tributes to Sala were paid before the match, which Cardiff won 2-1, with both sets of players observing a moment's silence.