The final arguments in prominent Hong Kong activist Jimmy Lai’s national security trial have been postponed after his lawyer said he experienced heart palpitations and the judges wanted him to receive medical treatment first.

Hailed by some as a hero and scorned by others as a traitor, Hong Kong's pro-democracy media tycoon Jimmy Lai is in the final stage of his national security trial. Closing arguments were scheduled to start on Thursday for Lai, who is accused of colluding with foreign forces under a Beijing-imposed national security law.