FBI investigates Lohan 'stalker' threats

The FBI is reportedly investigating claims that Lindsay Lohan has been threatened in rehab.

The actress is currently undergoing treatment at the Betty Ford Centre in California.

Last week, it was reported that Lohan was moved to a more secure location to continue her rehabilitation after she received threatening text messages and phone calls.

According to TMZ, the FBI is now in possession of them.

It is thought that Lohan's parents have also been receiving harassing messages. Her mother Dina passed along those sent to her to the FBI for analysis.

Some of Lindsay's friends apparently believe that the messages are from Sam Lufti, the former manager and friend of Britney Spears.

Los Angeles Superior Court issued a three-year restraining order against Lufti last year, ordering him to stay away from Spears after the singer's father called him a "predator".

Lufti has allegedly been in contact with Lindsay's father Michael.