Methods, a wireless device (110) and a radio network node (120) for managing a control block are disclosed. An extended Temporary Flow Identifier, eTFI, is assigned to the wireless device (110) by the radio network node (120). The radio network node (120) constructs the control information. The radio network node (120) performs a bit-wise modulo two addition with a control block and a combination of the eTFI and a pre-determined bit pattern to obtain a modified control block. The radio network node (120) adds channel coding redundancy. The radio network node (120) maps the modified control block onto physical resources. The radio network node (120) sends the modified control block to the wireless device (110). The wireless device (110) decodes the received modified control block removing the channel coding redundancy, performs a bit-wise modulo two addition between the modified control block and a combination of the eTFI and a pre-determined bit pattern to obtain a control block. The wireless device (110) decodes the control block using FIRE-decoding to obtain the control information. The wireless device (110) determines it is the intended recipient of the control information if the TFI information therein matches its assigned TFI. Corresponding computer programs and carriers therefor are also disclosed.