An international student who earned his law degree in the U.S. was arrested and driven away by plainclothesmen after he returned to Azerbaijan, provoking outrage among civil society activists.

Hours after Emin Aslanov was detained in downtown Baku on Monday, he reappeared at the Narimanov district court and was sentenced to 30 days in jail on charges of "disobeying the police," witnesses said.

Civil society activists quickly condemned the Azerbaijani government, saying the arrest was politically motivated.

In a public appeal, dozens of activists called for Aslanov's immediate release.

"We know Emin Aslanov as a professional lawyer and as one of the most distinguished young persons," activists said in a statement. "We can confidently state that he has not committed any crime."

The Azerbaijani government has not issued any statement on the arrest or responded to the condemnation.

An outspoken defender of human rights in his native country, Aslanov had returned to Azerbaijan four days earlier, after completing his studies at Syracuse University in upstate New York.

'Deeply distressing'

"Emin Aslanov was my first Azerbaijani student and [his arrest] is deeply distressing," Cora True-Frost, one of his professors, told VOA via Skype.

She spoke about the widespread concern among the university faculty and students regarding the arrest of the alumnus in a country frequently criticized for politically motivated arrests.

True-Frost, who said she was a former human rights advocate, advised that "all concerned people try to keep Emin in public scrutiny and be aware of his situation so that there might be pressure put on the Azerbaijani government to provide him with an open trial, due process and the opportunity to have the charges made against him public and the evidence that supports those charges made public."

Aslanov's arrest and reappearance in court echoed the arrest of journalist Afgan Mukhtarli in May 2017. The investigative journalist went missing from Tbilisi, Georgia, and appeared in a detention facility in Baku a day later. He was sentenced to six years in prison on numerous charges, including illegal border-crossing.

According to Amnesty International, Azerbaijani authorities arbitrarily arrest and detain dissidents, independent journalists and bloggers.

The government of Azerbaijan denies holding political prisoners, but Azerbaijani human rights defenders estimate that more than 150 people remain in prison on politically motivated charges.