Some 2,000 Turkish riot police were on standby Monday as four of their colleagues stand trial for allegedly beating to death a 19-year-old student during three weeks of anti-government protests last June.

The high-profile court case comes as Prime Minister Recep Tayyip Erdogan battles his biggest crisis in 11 years in power, hitting the economy and threatening the strongman's presidential ambitions.

Pummelled with baseball bats and truncheons in the western city of Eskisehir on June 2, Ali Ismail Korkmaz was one of six people to perish as nationwide protests convulsed 80-million-strong Turkey.

In an attack recorded by security cameras, the student, wearing a "World Peace" T-shirt, suffered a brain haemorrhage and died after 38 days in a coma.

Eight men, including four plain-clothes policemen, are accused of premeditated murder and face life in jail if convicted.

In an attempt to avoid fresh trouble, authorities are holding Monday's trial some 550 kilometres (350 miles) east of Eskisehir in Kayseri, but hundreds of demonstrators were still expected.

"My son will never come back but I want his killers punished," the dead student's mother Emel Korkmaz told Turkish media, saying she would attend the trial to "look them in the eye".

More than 8,000 people were injured, the Turkish Medical Association says, during protests in June that began as a peaceful sit-in against plans to build on a Istanbul park.

Erdogan called the demonstrators "vandals" and branded Twitter, used to organise protests, a "troublemaker". Heavy-handed police tools included tear gas, plastic bullets and even live ammunition.

Amnesty International said there were "gross human rights violations" and German Chancellor Angela Merkel -- hosting Erdogan in Berlin this Tuesday -- at the time called the police response "much too harsh".

Apart from a trial that began last year of a policeman -- facing five years -- for allegedly shooting dead a demonstrator in Ankara, police officers in the dock over the June violence has been a very rare sight.

The first court case involving demonstrators, meanwhile, is pencilled in for the first half of the year, with 255 expected to be tried, some of on "terrorism" charges.

Erdogan, 59, is now battling even bigger problems since a corruption scandal erupted in December implicating members of his inner circle in tales of backhanders, phone-tapping and gold-smuggling.

He has responded by sacking hundreds of police and prosecutors and accusing supporters of Fethullah Gulen, a friend-turned-foe Islamic preacher exiled in the United States, of waging a "dirty" conspiracy.

Erdogan is co-founder of the Justice and Development Party (AKP), the Islamic-rooted movement that has dominated politics since 2002, presiding over a booming economy and rising living standards.

But for critics, his handling of last June's protests and of the graft scandal have revealed something rotten about Erdogan's Turkey, once hailed as a model Muslim democracy and emerging economy.

Both episodes have also raised questions about Erdogan's hopes of being elected president in August -- he cannot run for another term as prime minister -- and much will depend on local elections in March.

Worries about Erdogan's stewardship have also contributed to the lira losing a third of its value in six months, prompting the central bank to hike interest rates last week -- despite the premier's protests.