A South Sudanese journalist has been abducted, tortured, burned and dumped near a graveyard, according to local media reports, in the latest attack on the media in the country.

The assault on Joseph Afandy came as he recovered from being held for two months in detention without charge by security forces, after criticising the government’s handling of a two-year civil war.

Afandy, who was reportedly kidnapped on Friday by unknown men in a white vehicle with tinted windows, phoned for help after he was dumped near the graveyard.

“We found him in a bad condition - beaten and burned in his legs,” colleague Ibrahim Awuol told Juba’s Eye Radio on Tuesday.

The journalist is now recovering in hospital.

“We call on authorities to credibly investigate this horrible crime against our colleague, Joseph Afandy, to hold the perpetrators to account, and to ensure the journalist’s safety,” said Robert Mahoney of the Committee to Protect Journalists CPJ’s deputy executive director. “No one should have to endure what this young man has survived.”

Rights groups have accused the security forces of cracking down on journalists, stifling debate on how to end a civil war in which tens of thousands of people have been killed since December 2013.

Seven journalists were killed last year while covering the conflict. Some were caught up in the fighting but a reporter was shot in August in an apparently targeted attack. Peter Julius Moi was killed days after president Salva Kiir announced that journalists who reported “against the country” would be targeted.

Journalist George Livio, who worked for the UN-backed Radio Miraya in the town of Wau, has been in detention since being arrested in August 2014.

Reporters in Juba have described an Orwellian atmosphere in the country, saying only good news about the government is tolerated.

“It is very hard to maintain any level of professional standards here,” said a radio reporter who asked to remain anonymous. “We are only allowed to report about the positives without pointing out weaknesses or what needs to be corrected.”

Reporters Without Borders ranks South Sudan as 125th out of 180 countries in its 2015 world press freedom index.

• This article was amended on 10 March 2016 to clarify the meaning of the final sentence.