In a series of eight late-night voicemails released Wednesday by RadarOnline, Gibson is allegedly heard name-calling and swearing at his ex-lover Oksana Grigorieva, apparently after a tree-planting ceremony that day had turned sour.
A source close to Oksana tells PEOPLE that Gibson had become enraged after accusing her of flirting with a gardener at one of his Malibu properties, where the couple had met to bury their daughter Lucia's placenta on Feb. 18.
"You were a sour-faced bitch today," Gibson says in one voicemail he allegedly left on Oksana's home phone. "Do you think it was tricky to get that [expletive] tree in the hole, the placenta and organize that [expletive]? Do you know how much [expletive] time and money went into that? Did you thank me? Did you even have a [expletive] smile on your face? [expletive], no … You don't give a [expletive], do you? You really are a shallow bitch. Everything about you stinks, and I am seeing it real loud and clear."
According to RadarOnline, Oksana received about 30 phone calls from Gibson that night after she'd left the ceremony – and the relationship – that day.
Also on the tape, Gibson allegedly slams Grigorieva's beloved musical talent.
"You are just [expletive] ordinary," he says on the voicemail allegedly left on Oksana's home phone. "That goes for the talent too – it's ordinary. It's not extraordinary. It's pretty [expletive] common. I'd like to see you play a concert sometime. You make mistakes all over with live performances. You can't do it. So touring is out of the question for you, because you will [expletive] it up … So give it up."
With reporting by OLIVER JONES