She declined to speak to the media as she left the church, following a packed day that included a meeting with Zhang ­Xiaoming, head of Beijing’s liaison office in the city.

Reverend Dominic Chan Chi-ming, the vicar general of the diocese, offered the mass and told attendees about his prison visits to Tsang to give spiritual support.

The vicar general said he first went to meet Tsang at Lai Chi Kok Reception Centre after the former leader was convicted.

“The first thing I told him was, God has his meaning,” Chan said. “I held the hands of fellow brother Tsang to pray,” he said. “He’s still very concerned about Hong Kong affairs [and] developments.”

Tsang had been spending an “unprecedented” amount of time in prayer after he was sent to Stanley Prison, he added.

The mass was also attended by Bank of East Asia chairman David Li Kwok-po.

Democratic Party founding chairman Martin Lee Chu-ming, former chief secretary Anson Chan Fang On-sang, and former Civic Party lawmaker Audrey Eu Yuet-mee were also present, as was Edward Yau Tang-wah, director of the office of outgoing chief executive Leung Chun-ying.

Last month Tsang was jailed for 20 months after a jury convicted him of conspiracy to commit public misconduct.

The jury found him guilty of failing to disclose a conflict of ­interest over his approval of three applications from a radio broadcaster between 2010 and 2012.

At the time Tsang was in negotiations with broadcaster shareholder Bill Wong Cho-bau over a rental deal of a flat owned by ­another company of Wong’s.

Tsang is seeking appeal against his conviction.