Istanbul (AFP) - Around 200 people on Sunday gathered in Istanbul to honour the memory of murdered Saudi journalist Jamal Khashoggi.

Supporters met to talk and watch videos of eulogies for the Washington Post contributor who was killed inside the Saudi consulate in the city on October 2.

Turan Kislakci, head of the Turkish-Arab Media Association (TAM), to which Khashoggi belonged, called for justice to be done "so that these barbaric tyrants can never do the same thing again".

Yemeni human rights activist Tawakkol Karman, who won the 2011 Nobel Peace Prize for her participation in the Arab Spring uprisings, said the killing was reminiscent of crimes committed by the Islamic State Group.

Khashoggi was last seen entering the consulate on October 2 to obtain documents for his forthcoming marriage.

After repeated denials, Saudi Arabia finally admitted the 59-year-old had been murdered at the mission in a "rogue" operation.

Turkish pro-government daily Sabah on Saturday reported Khashoggi's killers poured the remains of the insider-turned-critic of Riyadh down the drain after dissolving him in acid.

Samples taken from the consulate drains showed traces of acid, Sabah said without quoting sources for its story.

Erdogan has accused the "highest levels" of the Saudi government of ordering the hit.

Some officials have pointed the finger at the all-powerful Crown Prince Mohammed bin Salman and some analysts say Ankara is keen to have the heir sidelined from the nexus of power in Riyadh.