A packet sub-engine coupled to a packet buffer determines which of multiple look up tables (LUTs) is to be searched for a matching entry that matches a received data packet. Each LUT corresponds to a different type of packet handling action and includes multiple entries, each with a match field and a corresponding collection of one or more actions for handling packets that match the match field. The packet sub-engine searches the determined LUT for a matching entry, processes the received data packet according to the action(s) in the matching entry, and determines whether a further LUT is to be searched for a further matching entry. The processed data packet is provided as an output if no further LUT is to be searched, or otherwise the packet sub-engine searches the further LUT and further processes the processed packet according to the action(s) in the further matching entry.