Detention of volunteers gives rise to fear over freedom of speech in former Portuguese colony

Authorities in the semi-autonomous Chinese city Macau have detained five organisers of an unofficial political referendum, amid fears of tightening restrictions on freedom of speech in the former Portuguese colony.

Soon after organisers opened an unofficial seven-day "civil referendum" on Sunday morning, police shut down electric polling stations across the city. They detained five volunteers, including Jason Chao Teng-hei, the leader of Open Macau Society, one of the vote's organisers. Chao was charged with "serious disobedience with police" and referred for prosecution. All five volunteers have been released.

The referendum, which was inspired by a similar ballot organised by Hong Kong activists in June, asked Macau residents if they were satisfied with the rule of Fernando Chui, the territory's chief executive, and whether they would support universal suffrage in future elections.

Currently, the chief executive is elected by an elite committee of 400 people, most of whom are business-focused and loyal to Beijng. Chui, the son of a construction tycoon, will almost certainly be re-elected next Sunday for a second five-year term. He has called the ballot unlawful.

As of Monday evening about 5,700 of Macau's 600,000 residents had cast votes.

"It is inherently illegitimate for personal information to be collected and handled for the purpose of the so-called civil referendum," Yang Chongwei, deputy coordinator of the Office for Personal Data Protection, a government agency, said at a press conference following the arrests. The office had warned the organisers before the vote opened that the ballot violated the territory's privacy law, according to local media.

The ballot asked for participants' phone and ID card numbers to prevent fraudulent voting. "We had asked [voters'] permission first before we collected their identity cards and related information," Bill Chou, vice president of the New Macau Group, another ballot organiser, told Reuters. "There is no reason for the police and other law enforcers to intervene and to arrest our people in charge."

Like its neighbour Hong Kong, Macau is officially a part of China but enjoys a free press, an independent judiciary, and civil liberties unknown on the mainland. Yet critics say that these freedoms have been slowly eroding under pressure from Beijing. Earlier this month Bill Chou Kwok-Ping, an associate professor of political science at the University of Macau, said the university would not renew his contract because of his social activism. Chou was elected vice president of the New Macau Association, the territory's most prominent pro-democratic group, in June. The university denied that he was suspended for his beliefs.

Another professor in Macau, Eric Sautedé of the University of St Joseph, was sacked in June, also ostensibly for his political outspokenness.

Although Macau residents are generally considered less politically active than their Hong Kong counterparts, the territory has been gripped this summer by a wave of political activism. In May 20,000 people gathered to protest against a bill that would give the chief executive power over the courts – perhaps the territory's biggest protest since 1999, when it was handed back to Chinese rule. The following month 2,000 people gathered to mark the 25th anniversary of Beijing's 1989 crackdown on pro-democracy protesters in Tiananmen Square.