Sri Lanka, Jan. 20 -- Alibaba founder Jack Ma has emerged after weeks out of the spotlight, which sparked speculation about his whereabouts as his companies face increased regulatory scrutiny.

Alibaba's Hong Kong-listed stock was up 5% on news of his reappearance.

Jack Ma just made his first public appearance in months as his tech empire continues to grapple with challenges from Chinese regulators.

The billionaire co-founder of Alibaba resurfaced Wednesday in a video published online by Tianmu News, a subsidiary of the Zhejiang government's official newspaper. Zhejiang province is home to Hangzhou, the city where Alibaba is based.

Ma had not made a public appearance or social media post since late October, just over a week before Alib...