The political wings of the Real IRA and INLA have denied making the death threats which a group has made to six young people in Creggan over the past fortnight.
The 32 County Sovereignty Movement (32CSM) and Irish Republican Socialist Party (IRSP) have also challenged the group behind the threats, Community Action Against Drugs (CAAD), to explain their actions.
The parents of two of the young people who rec
eived death threats recently have called for the threats to be lifted and for CAAD to explain the allegation they area making.
A spokesperson for the 32CSM - the political wing of the Real IRA - described the threats as "counter productive" and said they have "serious doubts" about the authenticity of group behind them.
"We have made strenuous efforts to make contact with this group about a number of concerns but on each occasion have drawn a blank. This leads us to have serious doubts about the authenticity and the motivation of this group," the spokesperson said.
The 32CSM also urged for CAAD to get in touch with other republicans, "We appeal to this group to approach the republican movement in order to clear up this confusion."
The IRSP also denied making the threats and said they are working with the families of those affected. "We are not aware who this group is and we would question their motives. They should make themselves known to other republicans and to the community they area claiming to protect.
"Young people who find themselves caught up in should be given the opportunity to come forward instead of facing threats like this. If any young people come forward to us they will be treated sensitively and confidentially," a spokesperson said.