They "were canoodling and being affectionate as she sat on his lap", an onlooker told US Weekly.
A source said: 'They were completely all over each other.
As per the sources, the two were "kissing all night".
Just a year ago The Weeknd was seen snogging Selena Gomez at Coachella and confirming their romance for all the world to see.
Bella and The Weeknd dated for over two years before splitting in November 2016.
Donovan Mitchell: Good to go for Game 2
George says this is the level at which he plans to hoop for the remainder of the playoffs. "I ain't never sit out playoff games". Head coach Quin Snyder didn't seem overly concerned as he said: "Everything that we know right now, he's fine ".
Also in attendance was Bella's newly single model sister Gigi Hadid but the beauty mostly kept to herself and 'wasn't seen flirting with any guys'.
"Wasted times I spent with someone else, she wasn't even half of you, ' the lyrics go in Wasted Times; "these girls only want you when you're winnin", but you've been with me from the beginnin".
With Selena since rekindling the spark with her ex Justin Bieber, fans got excited this week when it looked like The Weeknd might have done the same - speculating that Bella and The Weeknd might be getting back together.