As a result of Indonesia’s bloody 1965 communist purge and mass killings, as well as decades of anti-communist propaganda during Suharto’s New Order dictatorship, the “red scare” of communism remains very real in Indonesia and laws banning anything that could spread communist or socialist ideologies are still taken very seriously by some.

Related: Indonesia Defense Minister says raid on leftist books needed to prevent communist ‘revenge’

Some Indonesians take it so seriously, in fact, that they’ll go on vigilante raids and demand that books about the banned ideologies be removed from store shelves — without even bothering to read the books first to know whether or not they actually support those ideologies.

On Saturday, a group of men calling themselves Brigade Muslim Indonesia (BMI) arrived at a branch of Gramedia, the country’s largest bookstore chain, at Trans Mall Makassar in South Sulawesi. The BMI group conducted a “sweep” (a term often used in Indonesia to describe searches conducted by vigilante groups) of the bookstore and posted a viral video showing themselves with several books dealing with subjects such as Marxism and Leninism and demanding that they be removed from Gramedia and returned to their publishers for violating the law.

“We have been searching for radical books which are actually prohibited by law,” one of the men in the video says.

“It is believed that books such as this are part of the spread of that understanding and thank God we are working with Gramedia now to withdraw these books and return them to the printer. We agree that Makassar must be free from Marxism and Leninism,” he continued.

Local news outlet Tirto identified two of the books targeted by BMI as Pemikiran Karl Marx: Dari Sosialisme Utopis ke Perselisihan Revisionisme (Karl Marx’s Thoughts: From Utopian Socialism to the Dispute of Revisionism) and Dalam Bayang-Bayang Lenin: Enam Pemikiran Marxisme dari Lenin sampai Tan Malaka (In the Shadows of Lenin: Six Thoughts on Marxism from Lenin to Tan Malacca).

Both books were written by Franz Magnis-Suseno, a Catholic priest and professor of philosophy. In fact, Father Magnis, who has studied the life and works of Karl Marx extensively as his academic field of research, is highly critical of Marxism.

As noted by Detik, Father Magnis explicitly says Marxism is not compatible with modern democracy and pluralism, describing it as a fossil of a bygone era. But he also argues in his books that Indonesians need to be able to understand Marxism from a critical and historical perspective.

The laws that ban the spread of Communism and Marxism-Leninism in Indonesia forbid any activities that could propagate their ideologies. The vague wording of the law could potentially criminalize the dissemination of neutral or even critical information regarding the banned ideologies, but last year Indonesia’s minister of research, technology and higher education, Mohammad Nasir, said that there was no problem with Indonesian students studying about communism or related ideas from a historical perspective in an academic setting.

A representative of Gramedia told news outlets that the BMI group did not confiscate any of the books in question but did confirm that their members demanded the titles be removed from shelves. He did not say whether or not the titles would be removed but said that any such decision would require further study and input from authorities.

Detik asked the head of the BMI group, Muhammad Zulkifli, if anybody in his group had actually read the books they demanded be removed to know if they actually supported Marxism. He admitted they had not but said the descriptions on the outside of the book were sufficient.

“We could not open the books because they were sealed, but their synopses do indeed include explanations on the thoughts of Karl Marx. So we assume and suspect there are indications (of propagation),” Zulkifli said, claiming that his group was working in coordination with local law enforcement.

However, a spokesperson for the South Sulawesi regional police said that they were going to investigate BMI over the raid as only law enforcement officials had the legal authority to conduct such searches for illegal materials.

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