Embattled actor/director Mel Gibson met with Los Angeles Country Sheriff's investigators on Sunday for a formal interview about allegations that former girlfriend [article id="1643298"]Oksana Grigorieva tried to extort him[/article] by threatening to go public with allegations of domestic abuse and leaking his now infamous series of recorded telephone rants.

According to the Los Angeles Times, Gibson, 50, who is currently being [article id="1644089"]investigated for alleged domestic violence and child endangerment[/article], spoke to the detectives only about the extortion allegations against Grigorieva.

"He wanted to make formal complaint for the allegations for extortion and provide information to the detectives," according to sheriff spokesman Steve Whitmore. "Detectives will investigate this wherever it leads." The meeting with Gibson follows one last week with the "Lethal Weapon" star's lawyers, who presented evidence to the sheriff's investigators that they said supported the claims of extortion. According to the Times, the attorneys also revealed that Grigorieva was after a multimillion-dollar payout when the couple split up earlier this year. Gibson has yet to speak publicly about the tapes and his representatives have not denied that it is his voice heard on the shocking recordings.

Last Friday, Grigorieva adamantly denied the allegations of extortion, saying, "Because Mel is lying. He is lying. There is no extortion. There's is no texts and no emails. ... I am fighting for my child. He's just a liar, and it will come in the court, just wait." And, after reports surfaced that her sister might have been the source of the leaked tapes -- in which a sometimes out-of-breath [article id="1642912"]Gibson can be heard yelling racial and sexist slurs[/article] at Grigorieva and [article id="1644258"]seemingly threatening her life[/article] -- the aspiring Russian singer also [article id="1644333"]denied that her family was the source of the leaked recordings[/article] that have been posted by the gossip site RadarOnline.

People magazine reported magazine reported that Gibson is being extra careful these days, even asking for an independent observer to monitor his visits with the couple's nine-month-old daughter. The action was not ordered by the court, but Gibson wanted an unbiased observer to witness his interactions with the infant, an unnamed source said, so "Oksana couldn't lie."

The unidentified observer, who has family law-related credentials and was cleared by the Department of Children and Family Services, was present over the weekend when Gibson and the child spent time at the actor's private church. While Gibson is allowed unsupervised visits with his daughter, he voluntarily requested the monitoring to avoid any other issues in the increasingly nasty custody battle over the child.

In addition to the domestic violence and extortion court cases, TMZ reported that Grigorieva is also preparing to battle her ex over the rights to her unreleased music. Citing unnamed sources close to Grigorieva, 40, the site claims that she is prepared to sue Gibson in order to secure the rights to release a new CD's worth of music that he executive produced and co-wrote.

TMZ said that Gibson -- who can be heard on a number of the recordings released so far [article id="1643752"]complaining about money[/article], specifically the millions he claimed to have spent on Grigorieva's stalled music career -- is not likely to sign over publishing rights on the songs anytime soon. The battle over the music could end up being part of whatever financial agreement the couple arrives at once the dust has settled from their various court cases.