Indonesian police said they have arrested five people in connection with the murder plot [Anton Raharjo/Anadolu]

Indonesian police have arrested a businessman for allegedly ordering the killing of two journalists in the northern Sumatra province.

The bodies of the journalists, Maraden Sianipar and Maratua Siregar, who were mediating a land dispute between the businessman’s company and local residents, were found with multiple stab wounds in Labuhan Batu area last week, police said on Saturday.

Businessman Wibharry Padmoasmolo was arrested for allegedly masterminding the plot by paying almost $3,000 to four men to commit the killings.

Padmoasmolo allegedly owns a firm that produces palm oil – a widely used vegetable oil found in everything from soap to chocolate – which was in a dispute with locals that the two victims were advocating for, police said.

The killings were aimed at stopping the pair’s involvement, according to authorities, who added that Padmoasmolo has denied owning the firm under questioning.

“The suspects asked the victims why they had come to the plantation before a quarrel broke out, which ended in murder,” said the North Sumatra police chief, Agus Andrianto, according to the local paper Jakarta Post.

In all, five people have been arrested in connection with the murder plot and police said they are still searching for several more suspects still at large.

Victims Sianipar and Siregar worked together for a local online news portal before going freelance in 2017.

A friend of Siregar said they had recently become known for their activism in land disputes – a common source of conflict across the resource-rich Southeast Asian archipelago.

The friend said Siregar was active in an organisation that advocated for residents in the dispute.

Many cases of violence against journalists in Indonesia go unsolved, according to the Alliance of Independent Journalists, which has reported at least two dozen cases this year alone.

Indonesia is ranked 124th out of 180 countries on the 2019 World Press Freedom Index published by Reporters Without Borders.