An Iranian cancer researcher has been denied entry to US

An Iranian cancer researcher flew to the US on Tuesday with his wife and three small children to conduct postdoctoral research but says he was denied entry and deported with his family.

Mohsen Dehnavi, who holds a visiting work visa, was traveling to the US to conduct research at Boston Children's Hospital, affiliated with Harvard University.

They were stopped by the immigration police at Boston's Logan International Airport and deported the next day, Dehnavi told state broadcaster IRIB at Tehran airport on Wednesday night.

"The US government, with the new restrictions on Iranians, did not let us enter although the goal of our trip was scientific and our research was aimed at saving cancer patients," he said.

Dehnavi said the police detained them for 30 hours without any outside contact and confiscated his research equipment and laptop.

"They said it is clear to us that you are a top scientist in children's cancer treatment which is a completely humane, non-military and non-dangerous field, but we cannot allow you into the US due to existing security protocols," he said.

Dehnavi said he had been in contact with Harvard for two years and obtained his visa in March.

According to the archives of the conservative Fars news agency, Dehnavi was head of the Basij militia at the prestigious Sharif University in 2007.

Iran's vice president for science and technology, Sorena Sattari, said the researcher had been deported on the basis of "unconventional excuses" and that it was cancer patients who would suffer the consequences, Tasnim news agency reported.

Former US Secretary of State John Kerry said of the incident, "[t]his is not who we are."

"A doctor comes to the US to save lives and this happens. This is not who we are," he wrote in a tweet Wednesday in response to an article on the case in The Boston Globe.

The US Supreme Court last month reinstated a modified version of President Donald Trump's travel ban on citizens from six predominantly Muslim countries including Iran.

Trump says the ban is needed to keep "terrorists" out of the country but Tehran has called it "truly shameful."

The Basij paramilitary volunteer force, established by Ayatollah Ruhollah Khomeini after the 1979 revolution, played a key role in crushing opposition protests in 2009.

Largely recruited from among young Iranians, the militia also plays an important social role, being deployed in vaccination campaigns and relief efforts after earthquakes and other natural disasters.

In 2013, Dehnavi was a key campaign official of Saeed Jalili, a hardline opponent of President Hassan Rouhani in the presidential election, according to Fars and Khabar Online reports at the time.