Maria was still at the Convent when the application for a stay of execution, pending appeal, was heard on 11 December. She did not appear in court. She could not influence what was going on or what was about to happen as events moved inexorably to their climax for herself and for many others.

From early morning, people began to gather around the Supreme Court. Some carried white cloth banners demanding Maria's removal from the Convent, others a green flag displaying a crescent and star. They shouted slogans. By the end of the hearing, about noon, the crowd had become a restive mob of 2,000 to 3,000.

Disorder broke out soon afterwards outside the Supreme Court. In the afternoon, it moved to the vicinity of the Sultan Mosque. After nightfall there were outbreaks in other, fairly far-spread, parts of the island.

Rioting was at its worst on the first afternoon and night. It continued on a declining scale until noon on 13 December.

Eighteen people were killed – nine by the rioters and nine shot by the police or military. One-hundred and seventy-three were injured, many seriously. Nearly 200 vehicles were burned or damaged. Most of those killed or injured by rioters were Europeans or Eurasians.

A Commission of Inquiry was appointed by the Governor to report on the riots. It consisted of Sir Lionel Leach, a member of the Judicial Committee of the Privy Council, as Chairman, with Sir Henry Studdy, Chief Constable of the West Riding of Yorkshire and Mr. J.H. Wenham, Chairman of the Standing Committee of Surrey, as members. Mr. J.R. Williams was Secretary.

The Commission ascribed the first disorders outside the Supreme Court to the religious passions whipped up over Maria's case but found that later outbreaks elsewhere were racial in character, directed indiscriminately against Europeans and Eurasians.

The rioters were mainly Malays but they included many overseas Muslims. The Commission found no evidence of communist inspiration behind the rioting, which apparently took the Malayan Communist Party by surprise. Some Chinese youths joined in, notably a criminal band known as the “108 Gang”, but their part was opportunist and minor.