A dozen black holes may lie at the centre of our galaxy, the Milky Way, researchers have said.
A new analysis provides support for a decades-old prediction that "supermassive" black holes at the centres of galaxies are surrounded by many smaller ones.
However, previous searches of the Milky Way's centre, where the nearest supermassive black hole is located, have found little evidence for this.
Details appear in the journal Nature.
