Turkish police on Friday put Istanbul under a security lockdown to to stop unauthorized demonstrations going ahead on May Day.

The normally traffic-clogged streets in the city centre were quiet as the authorities blocked off all vehicle access to Taksim Square.

In May and June 2013, the square became the focus of deadly anti-government protests.

However, the demonstrations started off peacefully at one of Istanbul's famous landmarks, Gezi Park.

Sit-ins were staged over plans to build commercial properties on the historic public space, but the movement soon became a platform to oust the government of Prime Minister Recep Tayyip Erdogan.

Taksim Square became a flashpoint for clashes on Labor Day following dozens of deaths there on May 1, 1977, when modern Turkey was going through one of its most turbulent periods.

The capital, Ankara, also had a heavy police presence on Friday, with restrictions on public access to the city centre.

Protests in defiance of lockdown

The Agence France Presse (AFP) news agency reported that several hundred people turned out in the Besiktas district on the Bosphorus - a strait that lies between European and Asian Turkey.

They were shouting "Long Live May 1!" and "shoulder to shoulder against Fascism!", as they gathered to march to Taksim Square, it was reported.

Concern over public demonstrations ahead of Turkey's June 7 legislative elections sparked Erdogan's administration to sanction the lockdown.

In a bid to discourage protests, Istanbul's main metro line has been halted several stops before Taksim and services on the city tram service are stopping halfway.

Iron barriers have been erected on the square itself making pedestrian access impossible.

Ferry services from the Asian side of the Bosphorus had been suspended to stop people from crossing to join protests on the European side.

Private helicopters were also banned from taking to the skies to give the airspace to police choppers.

AFP cited Turkish media, which reported that 20,000 police officers had been deployed in Istanbul backed up by 62 water cannon trucks, which would be used if clashes break out.

It's the first May Day since Turkey's parliament passed a controversial security bill this year giving the police greater powers to crack down on public protests.

lw/rc (AFP, dpa)