Is this an aftermarket remote entry/alarm system? If so, many of those have an option to flash the headlights and/or chirp the alarm to acknowledge the unlock command. If it is set up to do so that is why you lamp doors are opening/closing.
If this just started happening with the alarm system it is possible the programming or setup has changed to this mode due to a low battery, voltage transient, nearby lightning, or other cause of interference, or due to a poor power connection to the alarm unit.