LAPD investigators believe the $2-million jewelry heist at Paris Hilton’s Mulholland Estates mansion last month was probably done by someone familiar with the home’s layout and who knew how to access the socialite’s collection of rings, watches and necklaces.

Detectives are investigating a number of potential suspects based on information gathered from the scene and interviews with Hilton, who is cooperating with police.

Hilton’s bedroom was ransacked during the overnight burglary, but police sources said security video showed a thief who knew the home and was able to quickly find Hilton’s jewelry collection, which includes several family heirlooms. The jewelry was in a place that was not accessible to someone simply searching the home, police said.

The burglar entered through an unsecured door at the home in the 3300 block of Clerendon Road some time between late evening on Dec. 19 and 4 a.m. Dec. 20, according to police. Security guards discovered the break-in about 5 a.m. Dec. 20 and called police. Hilton was not home at the time of the burglary.

The thief wore gloves and shielded his face in a hooded sweat shirt. There was no evidence of the thief entering or leaving the gated community nestled in the hills of Sherman Oaks, law enforcement sources said.

Hilton provided descriptions of rings, watches and other pieces of jewelry. Sources said some of the pieces were very distinct and would be hard to sell.

In a brief television interview recently, Hilton suggested that she had some suspects in mind. “I think whoever did this, definitely has been [in my home] before. We have some suspects that I’m thinking of,” she told a reporter from E! News. “I would tell them to please return my things, because I know that they’re probably watching. . . . They just have to anonymously have a taxi drop it off in my front gate in a box,” she said. “They won’t get in trouble, but if all this goes on for much longer, they’re going to get in more trouble.”

Investigators said they did not believe the incident was connected to a string of burglaries in recent years that targeted celebrities and the wealthy on the Westside and in the Hollywood Hills.

In those cases, men dressed in black and wearing ski masks and gloves hit more than 70 homes in areas such as Bel-Air, Beverly Hills, Holmby Hills and the hills above Encino, usually at night and often on weekends.