The Maoists said this in a fresh audio message received by TV channels.
An expert who did not wish to be named believes it is unlikely the rebels will kill the 37-year-old legislator from Laxmipur constituency as he is a tribal and has a tribal support base, but feels they may ask him to resign from the assembly.
"They may also place some other demands," he told IANS.
Hikaka was abducted by the Andhra-Odisha border special zonal committee of the Communist Party of India-Maoist from the district of Koraput March 24.
The rebels were demanding the release of 29 people in exchange for his release but the government announced that only 13 would be freed.
The state government Thursday said a total of seven detainees have already filed their bail petitions and four of them have already got bail.
It also said two more detainees are also likely to be released soon.