Dozens of foreign and local journalists lit candles today to remember the 2009 murder of 32 journalists in the southern Philippines, the biggest recorded killing of media workers in history.

No one has been convicted of the murders. Wearing black shirts with the words "End Impunity", the journalists gathered outside a Catholic shrine in Manila, the site of two popular uprisings in modern times.

The journalists also protested against what they called growing press restrictions in the Philippines.

Melinda Quintos, head of the Center for Media Freedom and Responsibility, said there were "disturbing" developments that threatened freedom of the press. She cited the authorities' ban on coverage of the trial of the accused in the murder of the 32 journalists.

"The ban on media coverage of the trial is an unconscionable assault on press freedom -- the very right, so crucial to the state of democracy in this country," she said, adding that the trial was proceeding too slowly.

The court is still trying to resolve bail petitions four years after the case started. Meanwhile, four witnesses have been killed and lawyers say that defendants in the case have offered financial rewards to victims' families to withdraw the murder accusations.

A total of 192 people led by a powerful Muslim political clan are facing murder charges for killing 58 people, including the 32 journalists, and burying them on a hill in Maguindanao province in the southern Philippines.

Since August this year, police have prevented journalists from covering the trial for no apparent reason, Quintos added.

The Committee to Protect Journalists (CPJ), an independent organisation that promotes press freedom worldwide, has called the Maguindanao killings "the deadliest single attack on the press ever documented by the CPJ".

The victims were on their way to file a certificate of candidacy for a local politician standing in an election.

Foreign journalists joined today's protest, asking the government to explain an immigration ban on nine Hong Kong journalists who heckled President Benigno Aquino at an APEC meeting in Bali, Indonesia last year.

The state intelligence agency recommended the ban saying the journalists are considered a public safety threat.

The Philippines is one of the most dangerous countries in the world for journalists. Some 145 media workers have died since 1986 when democracy was restored after the ouster of Dictator Ferdinand Marcos.