Crackdowns on workers' protests in Istanbul, Tehran against May Day protesters
Six were arrested in Tehran during an unauthorised demonstration where workers gathered to protest the ban prohibiting them from marking the international labour day.
ILNA news agency reported that a security source said that the people arrested were "only those who wanted to cause trouble."
A union official, quoted by the news agency, said "the workers are not counter-revolutionaries or opposition members" but people who are merely seeking "a dignified life, a guaranteed job and minimum well-being".
Over 25 people were killed at the start of the year in Iran when protests broke out over the economy, which later changed into demonstrations directly challenging the government.
In Turkey, Istanbul police detained over 80 people and placed a security lockdown on the city as the Turkish metropolis marked a tense May Day.
Central Taksim Square was barricaded off completely by police forces, and aerial footage showed the usually busy urban space deserted apart from officers.
Another site of protest marches, Turkey's main shopping street, Istiklal Avenue, was also barred by officers.
Almost all shops and cinemas were closed and boarded up the length of the streets, and the public is expected to be able to pass through come evening.
Demonstrators who hoped to defy the protest ban in Taksim and marched towards the square were roughly apprehended and detained, with police officers pinning them to the ground according to an AFP photographer.
A total of 84 were arrested, according to the Turkish police, mainly from Besiktas area. Protesters were taken away in buses for questioning.
Political tensions are high in Turkey as the country prepares for snap elections on June 24.
Anadolu said that over 26,000 police were on duty in Istanbul supported by three helicopters, 85 water cannon vehicles and 67 armoured vehicles.