Lock arrangement and method for detecting the presence and location of a device sending a radio signal, which lock arrangement includes a lock case that can be fixed into a door, which lock case includes a locking latch and a latch mechanism. The lock arrangement further includes at least two antennas fitted into connection with the lock arrangement and a device for receiving radio signals connected to the antennas. The lock arrangement is able to determine on the basis of the signals measured from the antennas on which side of the lock arrangement the device sending a radio signal is located.