A jailed 71-year-old Chinese journalist appealed Tuesday against her seven year sentence, which triggered worldwide condemnation, as lawyers said China had imprisoned two other activists.

Dozens of police officers blocked access to the Beijing high court where Gao Yu appeared for an hour-long hearing "closed" to outsiders, her lawyer told AFP.

A former winner of Unesco's World Press Freedom Prize, her jailing in April for "leaking state secrets" was condemned by free speech advocates worldwide.

China's President Xi Jinping has in recent years overseen a crackdown on dissent which has seen hundreds of lawyers, activists and academics detained and dozens jailed.

The hearing came as two other political activists were sentenced to prison.

A court in southern China's Shenzhen jailed activist Yang Lin for three years for "inciting subversion of state power", his lawyer Fan Biaowen said.

Yang was associated with the "Southern Street Movement," a loose-knit group who held small protests calling for political reform. Several of its members have been jailed.

In the northeastern city of Harbin a lawyer for activist Chai Baowen said his client was given a three year sentence for "picking quarrels".

The charge was based on a single post Chai made on social media, criticising official accounts of a police shooting, attorney Yan Xin added.

- Not appropriate -

A Beijing court ruled in April that Gao leaked a 2013 directive by the Communist party named "Document number 9" to a Hong Kong media outlet.

The document warned of the "dangers" of multiparty democracy, independent media, "universal" definitions of human rights and criticism of the party's historical record, according to copies widely circulated online.

China's already close controls on the media have been further tightened, reporters say.

France-based Reporters Without Borders ranked China 176th out of 180 countries in its 2015 Press Freedom Index.

State security prevented journalists and around a dozen foreign diplomats from standing near the court, telling them it was "not appropriate".

Gao's jailing was condemned by human rights groups and free speech advocates, while Washington called for her "immediate" release and the EU demanded Beijing "review" her trial.

A consistent advocate for democracy and free speech, Gao was imprisoned following the government crackdown on student protests in Tiananmen Square in 1989.

Her political writings saw her jailed for six years in the 1990s, also on a charge of "leaking state secrets".

The journalist's lawyer Mo Shaoping said he did not expect the guilty verdict to be overturned by the tightly-controlled court when it ruled on the appeal "in a few days".

The septuagenarian has suffered from heart problems during her detention, but seemed "reasonably healthy", Mo said.

China slams UN for 'irresponsible' criticism of deportations
Geneva (AFP) Nov 23, 2015 - China on Monday accused the United Nations of making "irresponsible remarks" in its recent criticism of China, Thailand and Vietnam over deportations, insisting none of those deported were refugees.

Ravina Shamdasani, spokeswoman for the UN's Office of the High Commissioner for Human Rights (OHCHR), had on Friday told reporters that Thailand had deported two recognised Chinese refugees who had been due for resettlement in a third country.

Pointing to allegations of widespread torture in Chinese police custody, Shamdasani urged Thailand to stop deporting people, including potential refugees, to countries where they could face "an imminent risk of grave human rights violations".

But Beijing's mission to the UN in Geneva insisted the Chinese pair were not refugees.

"Two criminal suspects, illegally staying in Thailand and suspected of crime of organising other persons to secretly cross the national border, have been repatriated according to law," it said in a statement.

It added that the pair were suspected of endangering "national security" and had pleaded guilty, decrying that Shamdasani had "linked China-Thailand cooperation on combating transnational crimes with the so called refugee issue and 'torture' issue."

China said its cooperation with Thailand on the issue was "in conformity with international law and practice" and did not fall under the UN's Refugee Convention.

"Such hasty and irresponsible remarks went beyond the mandate of the OHCHR, to which China would like to express serious concern and dissatisfaction," it said.

The mission dished out the same criticism for Shamdasani's remarks on another case, in which Vietnam reportedly sent nine North Koreans, including a one-year-old and a teenager, to China -- North Korea's main ally.

Shamdasani had warned that the North Koreans may have been repatriated from China to their home country, "where they would be at risk of very serious human rights violations".

The UN urges all governments to refrain from returning people to North Korea, which stands accused of committing "systematic, widespread and gross" human rights violations.

The Chinese mission did not speak specifically of the nine, but insisted it had a right to deport North Koreans entering as illegal economic migrants.

"The OHCHR made irresponsible remarks on the cooperation between countries on the issue of illegal migration, referring to illegal migrants as refugees," it said.