Iran's Revolutionary Guards have carried out a new wave of arrests of cyber activists and members of pro-opposition social networking websites.

Kaleme, a leading opposition website, reported on Thursday that at least five Iranians who had shared news about the situation of political prisoners on Facebook have recently been held by the security apparatus of the country's elite forces. They were identified as Amir Golestani, Masoud Ghasemkhani, Fariborz Kardar, Seyed Masoud Seyed Talebi and Roya Irani.

According to Kaleme, some of the five Iranians were administrators of popular cultural and social pages on Facebook but had occasionally shared or published posts about the opposition Green movement and its members behind bars in Iranian prisons. The activists are being held in Tehran's notorious Evin prison.

Iran's English-language state newspaper, Tehran Times, also said on Wednesday that 16 people that officials have linked to "foreign agents" were arrested in the southern province of Kerman for crimes related to cyber offences.

"These individuals … are accused of acting against national security through co-operation with foreign networks and designing websites and developing content for counter-revolutionary websites with the aim of overthrowing the Islamic Republic system," said Ahmad Qorbani, Kerman's deputy prosecutor general, reported Tehran Times.

It was not clear if the five cyber activists were linked to the arrests made in Kerman.

Earlier in the week, a popular Iranian technology website, Narenji, said that seven of its employees, including journalists and technical staff, had been arrested by Revoultionary Guards. They are Aliasghar Honarmand, Abbas Vahedi, Alireza Vaziri, Nasim Nikmehr, Malihe Nakhaie, Mohammadhossein Mousavizadeh and Sara Sadjadpour.

Another opposition website, Sahamnews, also reported that Samad Khatibi, a film-maker and designer, who had been involved in the campaign supporting Hassan Rouhani for the presidential office, was arrested 10 days ago upon arriving in Tehran from the Netherlands. Sahamnews said Khatibi's family had been warned by the authorities not to speak to the media, adding that he still remains in custody.

It was not clear whether Khatibi or any of the 16 cyber activists arrested separately have had access to proper legal representation but political prisoners in Iran are often denied immediate access to their lawyers and their family members.

Rouhani ran for office on promises of bringing moderation back to the forefront of Iranian politics and pledged improvement in the situation of press freedom and social liberties in the Islamic republic. As the president assumed power, judicial authorities released a number of prominent political prisoners, including the acclaimed human rights lawyer Nasrin Sotoudeh, and gave others leave from prison.

But a large number of political prisoners are still being held in prison and the opposition leaders Mir Hossein Mousavi and Mehdi Karroubi remain under house arrests although they have never been put on trial.

Iran's Revolutionary Guards and the judiciary, controlled by Ayatollah Ali Khamenei, are independent of the Iranian government under Rouhani as well as the intelligence ministry. Many of the arrests in recent years of activists and politicians have been carried out independently by the revolutionary guards.

The arrests do not necessarily have the support of the government but the moderate president has so far kept muted over the new crackdown campaign.