Of the 4 people in custody ... 2 of them are 19-year-old men, one is an 18-year-old man and the other is a 34-year-old woman.
The female suspect is the MOTHER of one of the teenage men, according to LAPD Capt. Lillian Carranza.
And, that's not all ... cops believe there are more people involved in the burglaries and investigators are currently on the hunt to catch them too.
In total, cops say the burglary crew has already hit more than 24 homes -- with at least 12 more rich and famous targets in their sights.
The key to solving the case ... cops say Robert Woods' neighbor made the initial call to report the robbery at his house and when they found the first suspect, the found items connected to the other high profile cases.
In total, cops say the group stole more than $1 MILLION in property -- including $50,000 cash, watches, purses and a vehicle. Cops say one of the suspects also had a firearm.
Cops are asking the public to help strengthen their case against the suspects by identifying the stolen objects and giving information about the suspects and other possible crimes.