The present disclosure relates to methods and devices, of activating lawful interception. According to the present disclosure, a gateway comprises a controller for controlling, using a flow control protocol, the flow of packets through a switch controlled by the gateway. The switch receives (S11), from the controller, a lawful interception activation request, comprising a target identity; activates (S12), in response to said request, lawful interception on a target identified by the target identity; duplicates (S13), in the switch, packets targeting the target; encapsulates (S14) the duplicated packets with an additional header; and forwards (S15) duplicates from the switch directly to the lawful interception service provider entity (1) for further distribution to a Lawful interception Agency.