ISTANBUL (REUTERS) - Hundreds of Turkish riot police gathered on Tuesday on a major avenue leading up to Istanbul's Taksim Square where protesters have been staging demonstrations against plans to redevelop a park, a Reuters witness said.

Broadcaster NTV and other media outlets said the police were preparing to remove barricades which have been erected by the demonstrators in the area around Taksim Square, which has been the seen of violent clashes between police and protesters.