In situations in which an implantable medical device (e.g., a subcutaneous ICD) is co-implanted with a leadless pacing device (LPD), it may be important that the subcutaneous ICD knows when the LPD is delivering pacing, such as anti-tachycardia pacing (ATP). Techniques are described herein for detecting, with the ICD and based on the sensed electrical signal, pacing pulses and adjusting operation to account for the detected pulses, e.g., blanking the sensed electrical signal or modifying a tachyarrhythmia detection algorithm. In one example, the ICD includes a first pace pulse detector configured to obtain a sensed electrical signal and analyze the sensed electrical signal to detect a first type of pulses having a first set of characteristics and a second pace pulse detector configured to obtain the sensed electrical signal and analyze the sensed electrical signal to detect a second type of pulses having a second set of characteristics.