Here is a great article on the subject --- CLICK.
ARAFAT DEMANDED THE RELEASE OF ROBERT KENNEDY'S ASSASSIN. During the next two days, FEDAYEEN intercepts from PLO shortwave radios began pouring in from the Cyprus listening post, this time with clear orders from Arafat and his deputy, who were directing the hostage-taking from their Beirut headquarters. Arafat used a Racal Single-Side Band radio tuned to 7150 kHz to communicate directly with his other top deputy, Khalil Wazir (Abu-Jihad), who had been dispatched to Khartoum to carry out the kidnapping... [They demanded] the release of Sirhan Sirhan, THE PALESTINIAN WHO ASSASSINATED SENATOR ROBERT KENNEDY... Abu-Iyyad gave the order to execute the hostage...at around 8PM local time on March 2, 1973... Arafat himself came on the radio and reiterated the command to execute the American diplomats!"