UPDATE 1330 GMT: Academics from Iran’s leading associations in political science, sociology, peace studies, and cultural studies have written President Hassan Rouhani:

The news of the death of Dr Kavous Seyed Emami has astounded and shocked the scientific community and the environmental activists of the country.

In addition to being a well-known professor, a distinguished scientist and war veteran…he was a noble and ethical human being. The news and rumours related to his arrest and death are not believable….

Our minimum expectation is that you take immediate and effective action to seriously investigate the case … and make the institutions involved in this painful loss accountable.

Judiciary spokesman Gholam Hossein Mohseni Ejei stepped back from earlier regime assertion that Seyed Emami hung himself in detention: “I have heard he committed suicide, but I have so far no information on the details. This recent incident is under investigation.”

UPDATE 1045 GMT: Reports are circulating that Dr Kaveh Madani, the senior official in the Environment Ministry, has been released after a day in detention.

Observers initially pointed to a message this morning on Madani’s Twitter account — although that account has now been suspended.

Now the Environment Department’s website has posted a photo claiming to show Madani in a meeting today between the German Ambassador and Department head Isa Kalantari.

The Iranian regime’s crackdown on environmental researchers, scholars, and activists continued on Sunday with the arrest of a leading official in the Environment Department, Kaveh Madani (pictured).

Madani was an associate professor at Imperial College of London before returning to Iran in September as the Department’s deputy chief for international affairs and innovation. In December, he was celebrated by semi-official Iranian media for being named one of Europe’s four top scientists in 2016 by the European Union for Geo-Sciences.

The roundup of environmentalists began on January 24 with the detention of Dr. Kavous Seyed-Emami, an Iranian-Canadian dual national who is professor of sociology at Tehran’s Imam Sadeq University and the managing director of the Persian Heritage Wildlife Foundation.

On Friday, Seyed-Emami’s family was notified that he had died in custody in Tehran’s Evin Prison. Iranian officials said he had committed suicide by hanging, the same story they circulated after the deaths of two detainees in early January amid nationwide protests.

See Iranian-Canadian Academic Dies in Tehran Prison Under Interrogation

Tehran prosecutor Abbas Jafari Dolatabadi declared that the scholar “had made some confession and knew that others have also made confessions against him, so unfortunately he committed suicide in jail”.

The following day, Doulatabadi said other environmental activists had been seized: “These individuals were gathering classified information in strategic fields under the guise of scientific and environmental projects.”

According to relatives, at least nine other staff members and executives of the Persian Heritage Wildlife Foundation are being held. One, Morad Tahbaz, is an Iranian-American dual national; another is Niloufar Bayani, an advisor to the UN Environmental Program in Geneva for five years.

The detainees have had no phone contact with families or access to lawyers. “We really don’t know what they are accused of,” said a relative.

Gholamhossein Esmaili, the head of Tehran Province’s Justice Administration Chief, also said on Saturday that “a number of individuals who collected intelligence to hand over to foreigners have been arrested.” He added, “More arrests might be underway.”

A Death in Custody

Tehran MP Mahmoud Sadeqi, who first revealed the death in custody of Kavous Seyed-Emami, said he has asked Intelligence Minister Mahmoud Alavi for information, but has not had a convincing response.

Sadeqi, quoting a deputy intelligence minister, said Seyed-Emami was not arrested by the Intelligence Ministry and another intelligence organization must be involved. The MP said he would raise the case in Parliament on Monday.

An Iranian university lecturer said Seyed-Emami had been summoned to intelligence organizations several times, following a visit to Canada, before he was arrested.

Iran is beset by a series of serious environmental issues, including drought and the drying-up of lakes and rivers; deforestation; and health-threatening pollution in Tehran.